Aluminum and titanium, gallium can increase a + β / β transformation point . 10% aluminum phase transition point can be increased to about 1080 ℃. Gallium ability weaker . Aluminum titanium start improving recrystallization temperature of titanium alloys martensitic transformation start point (MS) is not affected. Excess aluminum and gallium in Ti3M generated based on the ordered phase a2 use temperature . Further , the aluminum present in the metastable β phase , phase to promote ω a phase transition ,titanium pipe thereby reducing the volume percentage of the time ω alloy phase.
Impact on the performance of aluminum and gallium , aluminum, titanium and gallium can improve the tensile strength at room temperature and high temperature has little effect on the high temperature plasticity. With increasing aluminum content of titanium - aluminum density and Poisson coefficient decreased linearly . Within the range of solubility , aluminum can effectively improve the elastic modulus of titanium , shear modulus, specific resistance and line expansion coefficient . When a2 phase, the emergence of a peak performance .
Titanium - appears to Ti3AL base of a2 ordered phase when the aluminum alloy , titanium alloy increases the tensile strength , ductility and toughness to deteriorate .titanium rod This ordered phase is often a similar role with Ti3AL resistant titanium alloys for high temperature Ti3Ga phase in phase .
tuoian
2013年12月30日星期一
2013年12月29日星期日
Some common β titanium and titanium alloys
Titanium - molybdenum titanium Department
Β titanium and molybdenum having the same lattice type and molybdenum in solid solution β titanium infinite . In a solution of molybdenum titanium at 600 ℃, 0.8% , when the molybdenum content exceeds 24 ~ 28% at 650 ℃ β single phase is formed . Ti - Mo binary system in the solid state is only a ~ β polymorphic transformation. In a titanium- molybdenum solubility of increase with decreasing temperature , titanium is not a supersaturated phase decomposition problem.
2 titanium - titanium vanadium
In the solid titanium shift occurred - exactly molybdenum . Vanadium and β have the same lattice type titanium , vanadium and titanium in the β solid solution is infinite . 600 ℃, vanadium and titanium in a solid solution of 3.5%. At 650 ℃, when the vanadium content of more than 18.5 % to 20% then form a single β -phase solid solution. In the liquid - solid transition , titanium - vanadium binary liquid line appears a minimum. Solubility of vanadium in a phase of decline in tandem with temperature increase , titanium is not a relative supersaturation and its decomposition problem.
3 titanium - niobium titanium Department
Its solid-state transformation and titanium - vanadium same liquid - solid transition similar to titanium - molybdenum . Niobium and titanium infinite β solid solution .titanium sheet Niobium at 600 ℃ in a solution of 4% of titanium , when the Nb content exceeds about 50% of the solid solution to form a single β . Its a / a + shape titanium β phase line - molybdenum similar. Nor supersaturated solid solution decomposition problem.
4 Titanium - Tantalum Department of titanium
Tantalum is also unlimited in β titanium solid solution . 600 ℃, a degree of solid solution of tantalum and titanium is 11 % when the content of tantalum is about more than 65% to form a single β solid solution.
5 titanium - iron- titanium
Β titanium iron solubility of 25% maximum , in 1085 ℃. The maximum solid solubility of iron in a 0.5% titanium , about 590 ℃ appear , the following occurs in the eutectoid transformation temperature , the solubility of the eutectoid point of about 15% . β = a + TiFe
6 titanium - . Manganese titanium
Its titanium-rich portion of the titanium - iron binary phase diagram of the Ti-rich part similar.titanium whole distributor The maximum solid solubility of manganese in the β titanium is about 33 % in 1175 ℃. The maximum solid solubility of manganese in a titanium of about 0.5% , in 550 ℃. Eutectoid transformation occurs at this temperature , the solubility of the eutectoid point of about 20% . β = a + TiMn
Β titanium and molybdenum having the same lattice type and molybdenum in solid solution β titanium infinite . In a solution of molybdenum titanium at 600 ℃, 0.8% , when the molybdenum content exceeds 24 ~ 28% at 650 ℃ β single phase is formed . Ti - Mo binary system in the solid state is only a ~ β polymorphic transformation. In a titanium- molybdenum solubility of increase with decreasing temperature , titanium is not a supersaturated phase decomposition problem.
2 titanium - titanium vanadium
In the solid titanium shift occurred - exactly molybdenum . Vanadium and β have the same lattice type titanium , vanadium and titanium in the β solid solution is infinite . 600 ℃, vanadium and titanium in a solid solution of 3.5%. At 650 ℃, when the vanadium content of more than 18.5 % to 20% then form a single β -phase solid solution. In the liquid - solid transition , titanium - vanadium binary liquid line appears a minimum. Solubility of vanadium in a phase of decline in tandem with temperature increase , titanium is not a relative supersaturation and its decomposition problem.
3 titanium - niobium titanium Department
Its solid-state transformation and titanium - vanadium same liquid - solid transition similar to titanium - molybdenum . Niobium and titanium infinite β solid solution .titanium sheet Niobium at 600 ℃ in a solution of 4% of titanium , when the Nb content exceeds about 50% of the solid solution to form a single β . Its a / a + shape titanium β phase line - molybdenum similar. Nor supersaturated solid solution decomposition problem.
4 Titanium - Tantalum Department of titanium
Tantalum is also unlimited in β titanium solid solution . 600 ℃, a degree of solid solution of tantalum and titanium is 11 % when the content of tantalum is about more than 65% to form a single β solid solution.
5 titanium - iron- titanium
Β titanium iron solubility of 25% maximum , in 1085 ℃. The maximum solid solubility of iron in a 0.5% titanium , about 590 ℃ appear , the following occurs in the eutectoid transformation temperature , the solubility of the eutectoid point of about 15% . β = a + TiFe
6 titanium - . Manganese titanium
Its titanium-rich portion of the titanium - iron binary phase diagram of the Ti-rich part similar.titanium whole distributor The maximum solid solubility of manganese in the β titanium is about 33 % in 1175 ℃. The maximum solid solubility of manganese in a titanium of about 0.5% , in 550 ℃. Eutectoid transformation occurs at this temperature , the solubility of the eutectoid point of about 20% . β = a + TiMn
2013年12月24日星期二
Grinding treatment process titanium and titanium plates
Grinding treatment process titanium and titanium alloys are divided into : mechanical polishing , ultrasonic grinding, mechanical composite electrolytic polishing , grinding barrels .
A mechanical polishing : high chemical reactivity of titanium , low thermal conductivity, viscous medical titanium plates, abrasive grinding machinery ratio is low, and easy to react abrasives , not for ordinary abrasive grinding and polishing of titanium , preferably good thermal conductivity superhard abrasives, such as diamond , cubic boron nitride , polishing line speed is generally 900 ~ 1800m/min appropriate, otherwise , the titanium surface grinding burns easily and micro- cracks .
Two ultrasonic grinding : by ultrasonic vibrations , so that the surface to be polished and the abrasive grinding between the polished surface and the relative movement is to achieve grinding and polishing purposes. The advantage is that the polishing tool than the conventional rotary groove portion becomes easier to nest and narrow , but also a large grinding effect is not satisfactory castings .
3 Electrochemical Mechanical grinding : the use of conductive abrasive , electrolyte and a voltage is applied between the grinding and polishing the surface , the joint action by mechanical and electrochemical polishing , reducing the surface roughness to improve the surface gloss. The electrolyte was 0.9NaCl, voltage is 5V, speed 3000rpm/min, this method can only be grinding plane , polishing complex denture is still in the research stage.
4 barrels of grinding : the use of centrifugal barrel polishing generated revolution and rotation , so that the barrel of the denture and abrasive friction relative movement serve to reduce the surface roughness of the grinding purposes. Polishing automation,titanium strip high efficiency, but can only reduce the surface roughness to improve the surface gloss, poor precision grinding , deburring available denture fine and coarse grinding and before polishing .
A mechanical polishing : high chemical reactivity of titanium , low thermal conductivity, viscous medical titanium plates, abrasive grinding machinery ratio is low, and easy to react abrasives , not for ordinary abrasive grinding and polishing of titanium , preferably good thermal conductivity superhard abrasives, such as diamond , cubic boron nitride , polishing line speed is generally 900 ~ 1800m/min appropriate, otherwise , the titanium surface grinding burns easily and micro- cracks .
Two ultrasonic grinding : by ultrasonic vibrations , so that the surface to be polished and the abrasive grinding between the polished surface and the relative movement is to achieve grinding and polishing purposes. The advantage is that the polishing tool than the conventional rotary groove portion becomes easier to nest and narrow , but also a large grinding effect is not satisfactory castings .
3 Electrochemical Mechanical grinding : the use of conductive abrasive , electrolyte and a voltage is applied between the grinding and polishing the surface , the joint action by mechanical and electrochemical polishing , reducing the surface roughness to improve the surface gloss. The electrolyte was 0.9NaCl, voltage is 5V, speed 3000rpm/min, this method can only be grinding plane , polishing complex denture is still in the research stage.
4 barrels of grinding : the use of centrifugal barrel polishing generated revolution and rotation , so that the barrel of the denture and abrasive friction relative movement serve to reduce the surface roughness of the grinding purposes. Polishing automation,titanium strip high efficiency, but can only reduce the surface roughness to improve the surface gloss, poor precision grinding , deburring available denture fine and coarse grinding and before polishing .
2013年12月23日星期一
The role of aluminum and gallium in titanium plates in
Aluminum and gallium are titanium with a titanium and β form substitutional solid solution, mainly from the solid solution strengthening effect . The standard rule of titanium , industrial pure titanium in addition , almost all contain a certain amount of aluminum.
A2 relative to control due to the occurrence embrittlement , aluminum and other elements considered with the precipitation of a2 , the concept of aluminum equivalent . In a titanium alloy , the aluminum equivalent of the following relationship :
AL `= AL +1 / 3Sn +1 / 6Zr +10 O` ≤ 8
Wherein , AL ` aluminum equivalent , AL, Sn, Zr weight percentage of these elements are in the alloy titanium axles. O ` elements affecting the gap , also called oxygen equivalent . Oxygen equivalent to :
O `= O + C +2 N
Where O, C and N are both of these elements in the weight percentage of titanium . When adding titanium silicon , aluminum equivalent should be:
AL `= AL +1 / 3Sn +1 / 6Zr +4 Si ≤ 8
In the practical application of these formulas have some effect.
In the heat treatable alloys β , in order to prevent the produce ω phase metastable β phase decomposition when caused by brittle , you need a certain amount of aluminum , usually around 3%.
Adding aluminum in titanium alloys can be formed by the middle of alloys with high melting point metal to prevent intolerable metallic inclusions , the ingot ingredients evenly. If 78% Mo Mo - aluminum master alloy melting point of molybdenum can be reduced to about 1900 ℃.
There are currently being developed to Ti3AL and TiAL new high-temperature titanium alloy as the base titanium pipe, but the actual industrial production from a certain distance .
A2 relative to control due to the occurrence embrittlement , aluminum and other elements considered with the precipitation of a2 , the concept of aluminum equivalent . In a titanium alloy , the aluminum equivalent of the following relationship :
AL `= AL +1 / 3Sn +1 / 6Zr +10 O` ≤ 8
Wherein , AL ` aluminum equivalent , AL, Sn, Zr weight percentage of these elements are in the alloy titanium axles. O ` elements affecting the gap , also called oxygen equivalent . Oxygen equivalent to :
O `= O + C +2 N
Where O, C and N are both of these elements in the weight percentage of titanium . When adding titanium silicon , aluminum equivalent should be:
AL `= AL +1 / 3Sn +1 / 6Zr +4 Si ≤ 8
In the practical application of these formulas have some effect.
In the heat treatable alloys β , in order to prevent the produce ω phase metastable β phase decomposition when caused by brittle , you need a certain amount of aluminum , usually around 3%.
Adding aluminum in titanium alloys can be formed by the middle of alloys with high melting point metal to prevent intolerable metallic inclusions , the ingot ingredients evenly. If 78% Mo Mo - aluminum master alloy melting point of molybdenum can be reduced to about 1900 ℃.
There are currently being developed to Ti3AL and TiAL new high-temperature titanium alloy as the base titanium pipe, but the actual industrial production from a certain distance .
2013年12月18日星期三
Effect of heat treatment on the properties of β titanium plates
β stabilizing element more dissolved β titanium , and to decrease the lattice parameter β titanium . β stabilizing element are raised to make room temperature tensile strength of pure titanium , while reducing the plasticity index elongation .titanium rod General eutectoid elements larger than the role of isomorphic elements.
With molybdenum , vanadium , niobium , and chromium, manganese, iron , cobalt, titanium impact of nickel on the elastic modulus and shear modulus of the crystalline elements eutectoid elements. In the quenched state , the peak value of the curve caused by the hardening phase ω . It makes elastic modulus, shear modulus and strength increases , the plastic lower .
Eutectoid β stabilizing element after adding titanium compound phase formed under certain conditions . However, the elements added slowly titanium eutectoid , compound phase is difficult to occur . Such as titanium - chromium system , TiCr2 often after long time to appear . In the system of analysis of the titanium element and the fast , sub-eutectoid alloy composition can be produced by the decomposition of the supersaturated phase a small amount of compound precipitated from the dispersion strengthening effect .
Improve β stabilizing element content , can keep more of β -phase alloys , can reduce sensitivity to hydrogen embrittlement . Further, in the two-phase alloy , the increase in the content of β stabilizing elements may also increase the hardenability of the alloy.
Mo can improve the thermal salt stress corrosion resistance of titanium alloys . Cobalt , palladium,titanium stockists molybdenum and niobium titanium in reducing medium can improve the corrosion resistance.
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With molybdenum , vanadium , niobium , and chromium, manganese, iron , cobalt, titanium impact of nickel on the elastic modulus and shear modulus of the crystalline elements eutectoid elements. In the quenched state , the peak value of the curve caused by the hardening phase ω . It makes elastic modulus, shear modulus and strength increases , the plastic lower .
Eutectoid β stabilizing element after adding titanium compound phase formed under certain conditions . However, the elements added slowly titanium eutectoid , compound phase is difficult to occur . Such as titanium - chromium system , TiCr2 often after long time to appear . In the system of analysis of the titanium element and the fast , sub-eutectoid alloy composition can be produced by the decomposition of the supersaturated phase a small amount of compound precipitated from the dispersion strengthening effect .
Improve β stabilizing element content , can keep more of β -phase alloys , can reduce sensitivity to hydrogen embrittlement . Further, in the two-phase alloy , the increase in the content of β stabilizing elements may also increase the hardenability of the alloy.
Mo can improve the thermal salt stress corrosion resistance of titanium alloys . Cobalt , palladium,titanium stockists molybdenum and niobium titanium in reducing medium can improve the corrosion resistance.
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Difference Analysis of titanium plates and titanium
Only pure titanium element , it is difficult in the general environment are generally in the presence of a titanium case ... compounds.
Even the market selling titanium metal jewelry , which can not be the real titanium is pure titanium. In the general case , the outermost layer of titanium would naturally thin titanium oxide.
Titanium dioxide is a compound itself already , titanium pipe and its chemical and physical characteristics are different from the original titanium , can not put together a comparison .
Due to the relative stability of titanium dioxide , so the market is to add titanium dioxide white paint to get pure white .... White ingredients also titanium dioxide.
Some use physical sunscreen skin care products , titanium dioxide is also used to achieve the effect of the sun .
Titanium dioxide titanium dioxide is called in the industry , the price is not expensive .... applications are very wide !
Titanium itself non-toxic , so the majority of the titanium compound is also related toxic .
Line of beauty in the material or related material coating lines , are easy to buy titanium dioxide. Currently titanium dioxide according to their molecular size, there is the general type and micron -type , or finer nanometer type ......
Although titanium dioxide itself is non-toxic,medical titanium bar but if you are using a nano -grade titanium dioxide, should be especially careful when using avoid inhalation of too much process titanium dioxide nano particles into the lungs !
Even the market selling titanium metal jewelry , which can not be the real titanium is pure titanium. In the general case , the outermost layer of titanium would naturally thin titanium oxide.
Titanium dioxide is a compound itself already , titanium pipe and its chemical and physical characteristics are different from the original titanium , can not put together a comparison .
Due to the relative stability of titanium dioxide , so the market is to add titanium dioxide white paint to get pure white .... White ingredients also titanium dioxide.
Some use physical sunscreen skin care products , titanium dioxide is also used to achieve the effect of the sun .
Titanium dioxide titanium dioxide is called in the industry , the price is not expensive .... applications are very wide !
Titanium itself non-toxic , so the majority of the titanium compound is also related toxic .
Line of beauty in the material or related material coating lines , are easy to buy titanium dioxide. Currently titanium dioxide according to their molecular size, there is the general type and micron -type , or finer nanometer type ......
Although titanium dioxide itself is non-toxic,medical titanium bar but if you are using a nano -grade titanium dioxide, should be especially careful when using avoid inhalation of too much process titanium dioxide nano particles into the lungs !
2013年12月16日星期一
Effect of hydrogen on titanium and titanium plates microstructure and properties
Hydrogen reducing titanium a + β / β transformation point is a gap β stabilizing element . Effect of hydrogen on titanium and titanium alloy performance mainly as hydrogen embrittlement .
Titanium and titanium alloys ,titanium sheet hydrogen can be dissolved in the β phase and a phase , you can also γ -phase (hydride ) form. In short , the different types of embrittlement different situation .
When titanium and titanium in hydrogen content of less than 0.020% , prevent the occurrence of hydride -based hydrogen embrittlement . But the stress-induced reversible hydride hydrogen embrittlement and hydrogen embrittlement in titanium and titanium alloys are difficult to avoid.
To reduce the hydrogen embrittlement of titanium and titanium alloys , the main measures is to reduce the hydrogen content . Practice has proved that the strict control of raw materials : vacuum melting , neutral or oxidizing atmosphere or a coating used in the processing ; heat treatment in a reducing atmosphere to avoid ; welding in an inert atmosphere or vacuum protection , to avoid increasing the alkali hydrogen acid etc. are valid. In addition , aluminum, tin can increase the solubility of hydrogen in a titanium in ; β stabilizing element by increasing the number of β phase to improve the solubility of hydrogen in titanium and titanium alloys , titanium and titanium alloys to reduce both hydride and stress-induced hydride -type hydrogen embrittlement sensitivity. But titanium oxygen is to promote hydrogen embrittlement .
The reaction is reversible titanium and hydrogen , and at 0.0004 mm Hg vacuum annealed at 600 ~ 900 ℃ 2 to 4 hours titanium wire, the hydrogen can reduce the content of titanium and titanium alloy to 0.01 % or less.
Titanium and titanium alloys ,titanium sheet hydrogen can be dissolved in the β phase and a phase , you can also γ -phase (hydride ) form. In short , the different types of embrittlement different situation .
When titanium and titanium in hydrogen content of less than 0.020% , prevent the occurrence of hydride -based hydrogen embrittlement . But the stress-induced reversible hydride hydrogen embrittlement and hydrogen embrittlement in titanium and titanium alloys are difficult to avoid.
To reduce the hydrogen embrittlement of titanium and titanium alloys , the main measures is to reduce the hydrogen content . Practice has proved that the strict control of raw materials : vacuum melting , neutral or oxidizing atmosphere or a coating used in the processing ; heat treatment in a reducing atmosphere to avoid ; welding in an inert atmosphere or vacuum protection , to avoid increasing the alkali hydrogen acid etc. are valid. In addition , aluminum, tin can increase the solubility of hydrogen in a titanium in ; β stabilizing element by increasing the number of β phase to improve the solubility of hydrogen in titanium and titanium alloys , titanium and titanium alloys to reduce both hydride and stress-induced hydride -type hydrogen embrittlement sensitivity. But titanium oxygen is to promote hydrogen embrittlement .
The reaction is reversible titanium and hydrogen , and at 0.0004 mm Hg vacuum annealed at 600 ~ 900 ℃ 2 to 4 hours titanium wire, the hydrogen can reduce the content of titanium and titanium alloy to 0.01 % or less.
2013年12月15日星期日
The role of hydrogen , nitrogen, carbon , boron, titanium plates in
The maximum solubility of oxygen in the β titanium is about 1.8% (6.0 atomic% ) , appeared in 1740 ℃. Titanium oxide in a solution of up to 6.8% maximum (18 atomic% ) , in the range of 900 ~ 1740 ℃. Below 900 ℃, when the alloy content exceeds 2.8% oxygen (8% atom ) , then turn compounds Ti6O, Ti3O, TiO , etc. appear. Titanium and oxygen interactions are reversible.
The maximum solubility of nitrogen in the β titanium was 1.9 % in 2020 ℃ + -25 ℃. Titanium in a nitrogen solid solution of about 6.85% maximum , in 1000 ~ 2350 ℃. There are two kinds of compounds : titanium stockists ε -phase and δ -phase . ε compound phase is based Ti4N or Ti3N phase , tetragonal lattice has a complex , a = 4.92 Å , c = 5.61 Å , c / a = 1.05. δ -phase TiN is based compounds. Interaction of titanium and nitrogen is irreversible .
The maximum carbon solid solution of β titanium is 0.8 % in 1750 + -20 ℃. A maximum degree of solid solution of carbon in titanium is 0.48 % in 920 + -3 ℃. Degree of solid solution of carbon in titanium or a titanium β are reduced with the temperature decrease . Titanium - the only one carbon-based compound phase , δ phase , which is a compound of the TiC -based .
The maximum solid solubility of boron in the β titanium is about 0.1% in 1670 + -25 ℃. The maximum solubility of boron in a titanium is approximately 0.05% , appeared in 886 + -4 ℃. The role of boron and titanium compounds can be generated Ti2B, TiB, TiB2 and Ti2B5 ,titanium standard parts the main compounds are TiB.
The maximum solubility of nitrogen in the β titanium was 1.9 % in 2020 ℃ + -25 ℃. Titanium in a nitrogen solid solution of about 6.85% maximum , in 1000 ~ 2350 ℃. There are two kinds of compounds : titanium stockists ε -phase and δ -phase . ε compound phase is based Ti4N or Ti3N phase , tetragonal lattice has a complex , a = 4.92 Å , c = 5.61 Å , c / a = 1.05. δ -phase TiN is based compounds. Interaction of titanium and nitrogen is irreversible .
The maximum carbon solid solution of β titanium is 0.8 % in 1750 + -20 ℃. A maximum degree of solid solution of carbon in titanium is 0.48 % in 920 + -3 ℃. Degree of solid solution of carbon in titanium or a titanium β are reduced with the temperature decrease . Titanium - the only one carbon-based compound phase , δ phase , which is a compound of the TiC -based .
The maximum solid solubility of boron in the β titanium is about 0.1% in 1670 + -25 ℃. The maximum solubility of boron in a titanium is approximately 0.05% , appeared in 886 + -4 ℃. The role of boron and titanium compounds can be generated Ti2B, TiB, TiB2 and Ti2B5 ,titanium standard parts the main compounds are TiB.
2013年12月13日星期五
The basic process of heat treatment of titanium and titanium plates
The basic process of heat treatment currently used mainly stress relief annealing, fully annealed and solution and aging treatment. Other annealing process, such as isothermal processing, multi-stage annealing process applications such as multi-stage aging rarely in production.
Stress relief annealing. The purpose is to eliminate stress relief annealing internal stress generated in the cold,titanium standard parts cold forming and welding and other processes. This mainly occurs during recovery, sometimes also called incomplete annealing. Stress relief annealing temperature is not too high, generally below the recrystallization temperature. Β-type titanium alloy can be heat treated to the recrystallization temperature can be below the temperature. But this time if more than a certain time often produce aging effects or aging effects caused by birth, and therefore the solution treatment is sometimes used to eliminate stress.
Elimination of the time required for stress relief annealing to workpiece thickness, small residual stress, and the annealing temperature used is desirable to eliminate the degree of stress. When considering the thickness of the workpiece reference to the case of stainless steel. As for the choice of temperature and degree of hope to eliminate stress generally be determined by experiment. Heating effect of temperature and holding time on TC4 titanium residual stresses. Obviously the heating temperature is high, the time required is short.
Stress relief annealing cooling method commonly used air cooling. For large size and shape complex parts can also be used furnace cooling. Stress relief annealing of titanium and titanium alloy system. Should be based on the above principles, as determined by the test within the recommended temperature and time range. It should be noted,titanium whole distributor stress relief annealing of titanium weldments often associated with subsequent heat treatment uniform consideration. Orthopedic and thermal stress relief annealing process for the cold forming parts, but should avoid contamination of the workpiece fixture.
Stress relief annealing. The purpose is to eliminate stress relief annealing internal stress generated in the cold,titanium standard parts cold forming and welding and other processes. This mainly occurs during recovery, sometimes also called incomplete annealing. Stress relief annealing temperature is not too high, generally below the recrystallization temperature. Β-type titanium alloy can be heat treated to the recrystallization temperature can be below the temperature. But this time if more than a certain time often produce aging effects or aging effects caused by birth, and therefore the solution treatment is sometimes used to eliminate stress.
Elimination of the time required for stress relief annealing to workpiece thickness, small residual stress, and the annealing temperature used is desirable to eliminate the degree of stress. When considering the thickness of the workpiece reference to the case of stainless steel. As for the choice of temperature and degree of hope to eliminate stress generally be determined by experiment. Heating effect of temperature and holding time on TC4 titanium residual stresses. Obviously the heating temperature is high, the time required is short.
Stress relief annealing cooling method commonly used air cooling. For large size and shape complex parts can also be used furnace cooling. Stress relief annealing of titanium and titanium alloy system. Should be based on the above principles, as determined by the test within the recommended temperature and time range. It should be noted,titanium whole distributor stress relief annealing of titanium weldments often associated with subsequent heat treatment uniform consideration. Orthopedic and thermal stress relief annealing process for the cold forming parts, but should avoid contamination of the workpiece fixture.
2013年12月9日星期一
Complete annealing of titanium and titanium plates
Complete annealing process , titanium and titanium alloys fully annealed purpose is to obtain a stable , good plasticity , or the overall performance corresponds to a certain microstructure . In this process, the main recrystallization , also known as the recrystallization annealing . In addition , there are also a phase and β phase composition, morphology and changes in the number . A majority and a + β titanium alloy is in the fully annealed condition to use. A two-phase titanium alloy whole area is very small, full annealing process occurs mainly recrystallization . Annealing temperature generally choose a + β / β transformation point 120 ~ 200 ℃. Overheating will cause unwanted oxidation and grain growth , incomplete recrystallization temperature is too low . Cooling rate has little effect on microstructure and mechanical properties of these alloys , the general air cooling.
Near a titanium and titanium alloys in a + β recrystallization annealing in addition , there is a phase and β phase changes in the composition, quantity and morphology to determine the annealing process is more complicated . Delivery status for metallurgical plant , the main requirements of stability and plasticity have good organization medical titanium plate. Annealing temperature generally choose a + β / β transformation point 120 ~ 200 ℃, cooling method also uses air cooling. But for the ultimate use of the product before annealing , the annealing process must be based on the impact on the microstructure and mechanical properties determined by experiment .
As metastable β -type titanium alloy , which is fully annealed solution treatment . Metallurgical plant manufactured before the annealing temperature is generally selected a + β / β phase transformation point 80 ~ 100 ℃. Within the recommended range of fully annealing process , the specific process should be determined by test basis processing history , the actual chemical composition, as well as equipment used in the material. In order to avoid unnecessary oxidation of the selection process should meet the performance requirements under the premise of using the lowest temperature and shortest time .
In recent years there has been β annealing process. a titanium alloy and a + β titanium alloys in air-cooled heat after β -phase region , the precipitation of coarse grains β needle ( or flake ) a. This organization corresponds to a high fracture toughness, creep resistance and notch sensitivity , but the plastic section shrinkage and other indicators declined . In the case of this performance can be emphasized as appropriate .
Moreover , for some alloys, when it is desired to improve the performance stability at the working temperature for a long time , are often higher than the temperature used in the second annealing temperature tittanium bar, or other treatment such as TC9 and tc6 alloys.
Near a titanium and titanium alloys in a + β recrystallization annealing in addition , there is a phase and β phase changes in the composition, quantity and morphology to determine the annealing process is more complicated . Delivery status for metallurgical plant , the main requirements of stability and plasticity have good organization medical titanium plate. Annealing temperature generally choose a + β / β transformation point 120 ~ 200 ℃, cooling method also uses air cooling. But for the ultimate use of the product before annealing , the annealing process must be based on the impact on the microstructure and mechanical properties determined by experiment .
As metastable β -type titanium alloy , which is fully annealed solution treatment . Metallurgical plant manufactured before the annealing temperature is generally selected a + β / β phase transformation point 80 ~ 100 ℃. Within the recommended range of fully annealing process , the specific process should be determined by test basis processing history , the actual chemical composition, as well as equipment used in the material. In order to avoid unnecessary oxidation of the selection process should meet the performance requirements under the premise of using the lowest temperature and shortest time .
In recent years there has been β annealing process. a titanium alloy and a + β titanium alloys in air-cooled heat after β -phase region , the precipitation of coarse grains β needle ( or flake ) a. This organization corresponds to a high fracture toughness, creep resistance and notch sensitivity , but the plastic section shrinkage and other indicators declined . In the case of this performance can be emphasized as appropriate .
Moreover , for some alloys, when it is desired to improve the performance stability at the working temperature for a long time , are often higher than the temperature used in the second annealing temperature tittanium bar, or other treatment such as TC9 and tc6 alloys.
2013年12月7日星期六
Titanium and titanium plates solid solution and aging treatment
When the solution plus a comprehensive aging heat treatment process . Solution treatment for aging effects and processes have a tremendous impact. Therefore , in determining the process must be integrated together to consider in order to get a satisfactory overall performance.
In nearly a titanium and β stabilizing element content smaller a + β titanium alloys ,medical titanium bars strengthening effect due to the tempering of martensite caused limited , requiring the organization after solution treatment on the overall performance should be better . Aging can only play a supporting role in strengthening . Such titanium process selection can refer to affect the heating temperature and cooling rate on microstructure and properties of TC4 titanium alloy .
At higher levels of β stabilizing element a + β titanium alloys , metastable β phase in aging decomposition can cause hardening, while the plastic drop. Accordingly , the organization requires plasticity after solution treatment is better .
Β titanium alloy can be heat treated to high temperature solution treatment and not only causes unnecessary oxidation of coarse grains , and make the decomposition time is a dispersed phase , the grain boundary area is narrowed light , resulting in a sharp decrease in ductility after aging . Solution treatment is too low to make the grain boundary bright areas widened even be uneven precipitation , resulting in no enhancement of the organization .
Solution treatment and aging plus titanium and titanium alloy solid solution treatment process . Listed within the process , still be based on the actual chemical composition ,titanium stockists a + β / β transformation point , the original organization before heat treatment equipment used and the like , the final heat treatment process to determine by experiment .
Titanium and titanium alloy produced in the solution process for the replacement of elements of martensite is supersaturated , does not cause as large as martensitic steel lattice distortion , titanium martensite is not so hard . Furthermore, the metastable β -phase is relatively low strength , and low temperature cold pre-aging before aging have greatly accelerated the rate of decomposition of the metastable β -phase .
In nearly a titanium and β stabilizing element content smaller a + β titanium alloys ,medical titanium bars strengthening effect due to the tempering of martensite caused limited , requiring the organization after solution treatment on the overall performance should be better . Aging can only play a supporting role in strengthening . Such titanium process selection can refer to affect the heating temperature and cooling rate on microstructure and properties of TC4 titanium alloy .
At higher levels of β stabilizing element a + β titanium alloys , metastable β phase in aging decomposition can cause hardening, while the plastic drop. Accordingly , the organization requires plasticity after solution treatment is better .
Β titanium alloy can be heat treated to high temperature solution treatment and not only causes unnecessary oxidation of coarse grains , and make the decomposition time is a dispersed phase , the grain boundary area is narrowed light , resulting in a sharp decrease in ductility after aging . Solution treatment is too low to make the grain boundary bright areas widened even be uneven precipitation , resulting in no enhancement of the organization .
Solution treatment and aging plus titanium and titanium alloy solid solution treatment process . Listed within the process , still be based on the actual chemical composition ,titanium stockists a + β / β transformation point , the original organization before heat treatment equipment used and the like , the final heat treatment process to determine by experiment .
Titanium and titanium alloy produced in the solution process for the replacement of elements of martensite is supersaturated , does not cause as large as martensitic steel lattice distortion , titanium martensite is not so hard . Furthermore, the metastable β -phase is relatively low strength , and low temperature cold pre-aging before aging have greatly accelerated the rate of decomposition of the metastable β -phase .
2013年12月5日星期四
Titanium , medical titanium plates anode coating
Iridium coated titanium , tantalum , titanium mesh anode products anodic oxygen evolution is a kind of resistance , mainly used in oxygen reaction , especially for acidic electrolyte , such as a certain concentration of sulfuric acid electrolyte , ultra-low oxygen titanium standard parts, oxygen can be used for electrolysis, chlorine is also resistant to corrosion, can be used to release oxygen and chlorine electrolysis, water electrolysis as it is an acidic reaction medium good oxygen electrode material , the electrode material in such a limited environment optional. The coated electrodes have been used in organic electrolysis, such as cysteine , glyoxylic acid, succinic acid , can be used Cr3 + + → Cr6 + electrolysis , water treatment for the organic electrolytic oxidation of indirect oxidation of organic matter in water and toxic substances, as the conversion of CN- . But also in the electroplating industry , as an auxiliary electrode , such as Cr -plated auxiliary anode , auxiliary anode copper , electrolytic zinc auxiliary anode , auxiliary anode cathodic protection , etc.
Ruthenium - Iridium - three yuan coated titanium anodes
The hydroxyl -containing coatings for high anode electrolyte , oxygen corrosion resistant , suitable for ion-exchange membrane electrolysis. Coating indicators:
1 , the discharge current density potential in 4000A/m2 1.18 volts (SCE).
2 , strengthen life ( coating weight loss method ) 1.02mv / 4 hours. cm2, life protection over five years , has been carried out in the industrial power slot.
Ruthenium - Iridium - tin - titanium (Ru-Ir-Sn-Ti) four yuan coated electrodes .
1 , low chlorine evolution potential , the potential is too small , the current density in the 2000A/m2 chlorine discharge potential is not greater than 1.12V, the overpotential less than 20mv.
2, the polarization current density of less than 30mv/10 units .
3 , to strengthen the long life 0.5N H2SO4, 1A/cm2 of current density , the life is greater than 1500 minutes .
The above three indicators are better than the industry specified target ( industry indicators: potential 1.13 V, the current density polarization 40mv/10 units , strengthen life of more than 1000 minutes ) . The coating has been widely used in the chlor-alkali industry , the actual life of up to 8 years.
Titanium mesh anode
The anode is a titanium mesh matrix, above the plating β-PbO2, which is characterized by ultra-high- oxygen titanium pipe, in acidic solution applications, especially some organic electrolysis, anodic oxidation reaction requires high potential , but also to minimize oxygen side effects , PbO2 electrode is a better material. Such as perchlorate electrolytic sewage treatment oxidation of organic matter , such as phenol-containing wastewater . It can also be used as a general release oxygen electrode , although its oxygen high, but its price is relatively Ta-Ir electrode is much cheaper , so in organic electrolysis , electroplating , sewage treatment and so many get applications.
Ruthenium - Iridium - three yuan coated titanium anodes
The hydroxyl -containing coatings for high anode electrolyte , oxygen corrosion resistant , suitable for ion-exchange membrane electrolysis. Coating indicators:
1 , the discharge current density potential in 4000A/m2 1.18 volts (SCE).
2 , strengthen life ( coating weight loss method ) 1.02mv / 4 hours. cm2, life protection over five years , has been carried out in the industrial power slot.
Ruthenium - Iridium - tin - titanium (Ru-Ir-Sn-Ti) four yuan coated electrodes .
1 , low chlorine evolution potential , the potential is too small , the current density in the 2000A/m2 chlorine discharge potential is not greater than 1.12V, the overpotential less than 20mv.
2, the polarization current density of less than 30mv/10 units .
3 , to strengthen the long life 0.5N H2SO4, 1A/cm2 of current density , the life is greater than 1500 minutes .
The above three indicators are better than the industry specified target ( industry indicators: potential 1.13 V, the current density polarization 40mv/10 units , strengthen life of more than 1000 minutes ) . The coating has been widely used in the chlor-alkali industry , the actual life of up to 8 years.
Titanium mesh anode
The anode is a titanium mesh matrix, above the plating β-PbO2, which is characterized by ultra-high- oxygen titanium pipe, in acidic solution applications, especially some organic electrolysis, anodic oxidation reaction requires high potential , but also to minimize oxygen side effects , PbO2 electrode is a better material. Such as perchlorate electrolytic sewage treatment oxidation of organic matter , such as phenol-containing wastewater . It can also be used as a general release oxygen electrode , although its oxygen high, but its price is relatively Ta-Ir electrode is much cheaper , so in organic electrolysis , electroplating , sewage treatment and so many get applications.
2013年12月3日星期二
Application of chemical medical titanium plates design
One-time investment of chemical titanium equipment , mainly because of the high price of titanium , but also because of the design and manufacturing aspects of the case . Currently, the economic benefits of chemical titanium equipment , mainly from the application process to play the comprehensive advantages . Therefore, the development of chemical titanium equipment , in addition to continuing to develop " chemicals used titanium" new areas , expanding the use of titanium equipment , but also the use of appropriate technology and ways to reduce one-time investment of titanium equipment , improve the use of the equipment reliability.
1 , applied research
1 ) to carry out theoretical studies of chemical titanium device designed to enrich and improve the induction of various data , organize work, you can now have the advantage of computing means to establish a more comprehensive database of titanium equipment design . Provide a sufficient basis for the optimum design and effective means of titanium equipment.
2 ) continue to carry out research titanium processing technology , such as welding and large containers lining technology.
3) the use of titanium equipment , maintenance and repair technology research for safety titanium equipment , effective use of the necessary means.
2, the design
1 ) as soon as possible to develop design specifications and standards of various chemical titanium equipment to ensure design quality, cost -saving design .
2 ) to promote " optimal design " technology.
3 ) Apply " Value Engineering " analytical material titanium cage configuration of equipment,titanium axles determine a reasonable way to use titanium .
3 , manufacturing
1 ) in the manufacturing process of titanium equipment , try to adopt new technologies, new processes, saving manufacturing costs.
2 ) strengthening the quality management equipment manufacturing , processing equipment and testing procedures to develop and improve the process to ensure product quality and maintain good titanium equipment " reputation ."
Domestic chemical industry to use titanium device has three sources, one homemade , the second is commissioned processing, the third is a combination of homemade and commission processing . Currently, nearly one hundred of titanium equipment manufacturing plant , and manufacturing level is key to ensuring the reliability of titanium equipment Inso . Surveys show that titanium equipment damaged more than half of the reason is due to poor manufacturing quality . Therefore , you should select a reasonable way to enable developers titanium equipment is guaranteed from the quality.
1 , due to the design and manufacture of titanium devices require specialized skills and the necessary means , therefore , to deal with the design and manufacture of titanium equipment qualification to be some form of recognition.
2 At present, the production of titanium chemical equipment has a certain scale and technological strength anium wire, therefore , can be implemented to take the point of production of titanium chemical equipment ; has a certain capacity for titanium chemical equipment production base, the application of funds and material sources to with the necessary support.
3 , the chemical composition of the appropriate form of titanium equipment development consortium titanium standard parts, to strengthen research , design, manufacturing aspects of horizontal linkages , simplifying the development process , to minimize development costs.
1 , applied research
1 ) to carry out theoretical studies of chemical titanium device designed to enrich and improve the induction of various data , organize work, you can now have the advantage of computing means to establish a more comprehensive database of titanium equipment design . Provide a sufficient basis for the optimum design and effective means of titanium equipment.
2 ) continue to carry out research titanium processing technology , such as welding and large containers lining technology.
3) the use of titanium equipment , maintenance and repair technology research for safety titanium equipment , effective use of the necessary means.
2, the design
1 ) as soon as possible to develop design specifications and standards of various chemical titanium equipment to ensure design quality, cost -saving design .
2 ) to promote " optimal design " technology.
3 ) Apply " Value Engineering " analytical material titanium cage configuration of equipment,titanium axles determine a reasonable way to use titanium .
3 , manufacturing
1 ) in the manufacturing process of titanium equipment , try to adopt new technologies, new processes, saving manufacturing costs.
2 ) strengthening the quality management equipment manufacturing , processing equipment and testing procedures to develop and improve the process to ensure product quality and maintain good titanium equipment " reputation ."
Domestic chemical industry to use titanium device has three sources, one homemade , the second is commissioned processing, the third is a combination of homemade and commission processing . Currently, nearly one hundred of titanium equipment manufacturing plant , and manufacturing level is key to ensuring the reliability of titanium equipment Inso . Surveys show that titanium equipment damaged more than half of the reason is due to poor manufacturing quality . Therefore , you should select a reasonable way to enable developers titanium equipment is guaranteed from the quality.
1 , due to the design and manufacture of titanium devices require specialized skills and the necessary means , therefore , to deal with the design and manufacture of titanium equipment qualification to be some form of recognition.
2 At present, the production of titanium chemical equipment has a certain scale and technological strength anium wire, therefore , can be implemented to take the point of production of titanium chemical equipment ; has a certain capacity for titanium chemical equipment production base, the application of funds and material sources to with the necessary support.
3 , the chemical composition of the appropriate form of titanium equipment development consortium titanium standard parts, to strengthen research , design, manufacturing aspects of horizontal linkages , simplifying the development process , to minimize development costs.
2013年12月1日星期日
How to medical titanium plates in the real sea change in galvanic corrosion
Galvanic corrosion behavior of electrochemical measurement parameter is the open circuit potential and galvanic current characterization of the two materials in contact titanium wire. The so-called open-circuit potential refers to the two materials temporarily off the meter coupling circuit to the reference electrode corrosion potential of each material were measured in the time. Due to the different degrees of polarization after coupling of different materials, the potential to achieve the basic stability of the different time after disconnection. Usually 1-20 minutes, the potential is measured after the stable potential. With the development of corrosion, the surface state of the material is also changing, and while the potential changes caused by changes in the behavior of galvanic polarization, ie corrosion kinetics changes. So we can come to understand variation of galvanic corrosion over time and the different electrical characteristics even on the track by open circuit potential measurements.
In the study of galvanic corrosion of titanium alloy parts can, first to see the real potential of the sea from rot titanium and other alloys from a thermodynamic point of view - time curve. All of these materials in the electrical potential in the real sea change over time. Especially stainless steel potential fluctuations and changes not only with the titanium is opposite tendency. Potential of titanium in all 20 days are rapidly being shifted over time, moving a rate of 200-300mV, but instead of stainless steel 1Cr18Ni9Ti rapid negative shift, moving magnitude of approximately 250mV. Copper alloys in seawater more stable full-B30 small potential fluctuation is small, but the overall trend is also a potential positive shift.
Seen from the curve, titanium potential shifts and more stable, while the stainless steel potential negative shift over time, it seems that with the stainless steel in just three months time cause corrosion perforation are intrinsically linked. Gillber and potential shifts Hefny think titanium has excellent corrosion resistance is due to the success of dense stable raw surface mechanical damage have a strong self-healing ability of TiO2: passivation film. We titanium E-pH diagrams and literature reports of knowledge, titanium chloride medium when pH> 2 does not occur when the activation area. For natural seawater pH was neutral to slightly alkaline is completely consistent.
Even for galvanic corrosion characteristics between pairs of titanium and titanium and even copper alloy, stainless steel between our TA2/BT14, TA2/B30 and TA2/18-8-ss three typical galvanic be analysis.
Galvanic corrosion specimen dimensions are 100 × 50 × 2mm, even for each group of three pairs of parallel samples were taken, even on the area ratio of 1:1. 104 days of trial.
According TA2/BT14 coupling measured open circuit potential - time curve, and galvanic current - time curve. May know, the open circuit potential curve has been in almost two titanium overlapped. medical titanium plate This shows that the coupling due to the polarization of the potential difference between the reduced and even disappear, although their corrosion potential difference of up to 150mV, would not exist galvanic corrosion.
According TA2/B30 even on the open circuit potential - time curve, and galvanic current - time curve. After the coupling of these two materials, TA2 potential positive shift dramatically, and B30, but fluctuate within a certain range, and a significant galvanic current. Another case, the outer channel potential difference is small, the galvanic current is not large, but there is an increasing trend to increase with time. It seems that localized corrosion of stainless steel from corrosion perforation caused by aggravated galvanic effect, the galvanic current rapidly increases. Thus, when titanium or stainless steel in contact with the B30, when their anode area ratio increased, galvanic effects will also increase, resulting Laqne early work also shows that this view.
In the study of galvanic corrosion of titanium alloy parts can, first to see the real potential of the sea from rot titanium and other alloys from a thermodynamic point of view - time curve. All of these materials in the electrical potential in the real sea change over time. Especially stainless steel potential fluctuations and changes not only with the titanium is opposite tendency. Potential of titanium in all 20 days are rapidly being shifted over time, moving a rate of 200-300mV, but instead of stainless steel 1Cr18Ni9Ti rapid negative shift, moving magnitude of approximately 250mV. Copper alloys in seawater more stable full-B30 small potential fluctuation is small, but the overall trend is also a potential positive shift.
Seen from the curve, titanium potential shifts and more stable, while the stainless steel potential negative shift over time, it seems that with the stainless steel in just three months time cause corrosion perforation are intrinsically linked. Gillber and potential shifts Hefny think titanium has excellent corrosion resistance is due to the success of dense stable raw surface mechanical damage have a strong self-healing ability of TiO2: passivation film. We titanium E-pH diagrams and literature reports of knowledge, titanium chloride medium when pH> 2 does not occur when the activation area. For natural seawater pH was neutral to slightly alkaline is completely consistent.
Even for galvanic corrosion characteristics between pairs of titanium and titanium and even copper alloy, stainless steel between our TA2/BT14, TA2/B30 and TA2/18-8-ss three typical galvanic be analysis.
Galvanic corrosion specimen dimensions are 100 × 50 × 2mm, even for each group of three pairs of parallel samples were taken, even on the area ratio of 1:1. 104 days of trial.
According TA2/BT14 coupling measured open circuit potential - time curve, and galvanic current - time curve. May know, the open circuit potential curve has been in almost two titanium overlapped. medical titanium plate This shows that the coupling due to the polarization of the potential difference between the reduced and even disappear, although their corrosion potential difference of up to 150mV, would not exist galvanic corrosion.
According TA2/B30 even on the open circuit potential - time curve, and galvanic current - time curve. After the coupling of these two materials, TA2 potential positive shift dramatically, and B30, but fluctuate within a certain range, and a significant galvanic current. Another case, the outer channel potential difference is small, the galvanic current is not large, but there is an increasing trend to increase with time. It seems that localized corrosion of stainless steel from corrosion perforation caused by aggravated galvanic effect, the galvanic current rapidly increases. Thus, when titanium or stainless steel in contact with the B30, when their anode area ratio increased, galvanic effects will also increase, resulting Laqne early work also shows that this view.
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