Titanium tube weld cracks and pores problems
Titanium tube weld crack problem
When the possibility of titanium welding, titanium round bar thermal cracking of welded joints is small, it is because few impurities in titanium and titanium alloys S, P, C , etc. , low melting point of S, P eutectic formed at the grain boundaries rarely generation, coupled with effective crystallization temperature range narrow, titanium and titanium alloy solidification when a small amount of shrinkage , weld metal does not produce heat cracks.
When titanium and titanium alloy welding, weld when an oxygen , nitrogen is high , the performance of the weld heat affected zone or become brittle in the larger weld stress, cold cracking occurs . Characterized by cracks in the weld called a few hours or even longer delay cracks. The study showed that the hydrogen diffusion welding process is the main cause of such cracks. Hydrogen in the welding process to a lower temperature by diffusion of the high temperature heat affected zone deep pool , the area increase the hydrogen content of the precipitates increased so that the amount of TiH2 , brittle heat affected zone is increased , the other due to volume expansion caused by precipitation of hydrides greater the stress , plus a hydrogen atom diffusion and aggregation to the high stress areas of the area, resulting in the formation of cracks . This delay prevents cracks approach is titanium industrial bar to reduce the welded joint main source of hydrogen .
Titanium tube weld porosity problems
When titanium pipe welding , porosity is often encountered a major problem. The root cause of the formation of pores is affected as a result of hydrogen .
Prevent blowholes process measures are:
1 ) in high purity argon welding , argon gas purity not less than 99.99%
2 ) the elimination of titanium tubes , oil and other oxide on the surface of titanium and titanium tubes eye organics . Can be cleaned with a chemical and mechanical methods.
3 ) subjected to the bath gas well , control the flow and the flow rate of argon gas , to prevent turbulence , impact protection.
4 ) Choose the appropriate welding process parameters, welding specification , increasing the residence titanium bar supplier time of deep pools to facilitate the use of air bubbles escape , which can effectively reduce porosity.
tuoian
2014年5月5日星期一
titanium bar stock Memory alloy pipe has been used in combination
Memory alloy pipe has been used in combination with automatic control ,
the sleeve may be made of shape memory alloy instead of welding , is
in the low temperature expansion of the tube to approximately 4% of the
full , a socket assembly with a heated , titanium bar stock shrinkage of the sleeve restore
the prototype , form a tight engagement . U.S. Navy aircraft hydraulic
system uses a 100,000 such joints, oil spills and damage over the years
never happened . Ship and submarine oil pipeline damage , repair it with
a shape memory alloy fittings, very convenient. In some parts of the
inconvenience of construction , the pin made of shape memory alloy ,
into the hole is heated to separate the trailing end automatically curl
to form single assembly .
Memory alloy is particularly suitable for thermo-mechanical and automatic temperature control , automatic opening and closing has made room arm can open the windows are in the sunshine during the day , automatically turns off when the night temperature drops. Memory alloy heat engine designs are also a lot that they can be in with a low temperature difference between the two media work , so as to take advantage of industrial cooling water , nuclear reactor heat, ocean thermal and solar power opened up titanium round bar new avenues . Now the problem is widespread efficiency is not high, only 4 % to 6% , to be further improved .
Memory alloys in medical applications is also very compelling. E.g., the bone with the bone plate , not only can two fixing broken bones , and the recovery of the original shape of the compression force is generated , forcing the broken bones are joined together . After straightening teeth using dental wire , long clip ligation of cerebral aneurysms and vas deferens , with the support plate straightening the spine , are implanted in the human body temperature by the action starts, thrombus filter is also a new product memory alloy . After being straightened filter implanted vein , will be gradually restored into a network , thereby preventing clot 95% flow to the heart and lungs.
Artificial heart is a more complex titanium industrial bar structure of the organ , muscle fibers of the elastic memory alloy thin film made of ventricular cooperate to mimic ventricular contraction . Now water is pumped been successful.
Memory alloy is particularly suitable for thermo-mechanical and automatic temperature control , automatic opening and closing has made room arm can open the windows are in the sunshine during the day , automatically turns off when the night temperature drops. Memory alloy heat engine designs are also a lot that they can be in with a low temperature difference between the two media work , so as to take advantage of industrial cooling water , nuclear reactor heat, ocean thermal and solar power opened up titanium round bar new avenues . Now the problem is widespread efficiency is not high, only 4 % to 6% , to be further improved .
Memory alloys in medical applications is also very compelling. E.g., the bone with the bone plate , not only can two fixing broken bones , and the recovery of the original shape of the compression force is generated , forcing the broken bones are joined together . After straightening teeth using dental wire , long clip ligation of cerebral aneurysms and vas deferens , with the support plate straightening the spine , are implanted in the human body temperature by the action starts, thrombus filter is also a new product memory alloy . After being straightened filter implanted vein , will be gradually restored into a network , thereby preventing clot 95% flow to the heart and lungs.
Artificial heart is a more complex titanium industrial bar structure of the organ , muscle fibers of the elastic memory alloy thin film made of ventricular cooperate to mimic ventricular contraction . Now water is pumped been successful.
2014年4月22日星期二
titanium bar for sale Titanium is an important structural metal
Titanium is an important structural metal in the 1950s developed, titanium because of its high strength, corrosion resistance, and high heat resistance, is widely used in various fields. titanium bar for sale Many countries recognize the importance of titanium alloy materials, have their research and development, and has been applied. 1950s and 1960s, mainly the development of high temperature titanium and titanium alloy airframe structures used in aircraft engine, the 1970s developed a number of corrosion resistant alloys, since the 1980s, corrosion titanium bar price resistance and high strength titanium alloy titanium further development. Titanium is mainly used for the production of aircraft engine compressor components, followed by structure rockets, missiles and high-speed aircraft
2014年4月15日星期二
titanium bar Metal Category
Metallurgical Industry Classification: Ferrous metals: iron, chromium, manganese and three kinds of non-ferrous metals: aluminum, magnesium, potassium, sodium, calcium, strontium, barium, copper, lead, zinc, tin, cobalt, nickel, antimony, mercury, cadmium, bismuth, gold, silver, platinum, ruthenium, rhodium, palladium, osmium, iridium, beryllium, buy titanium bar lithium, rubidium, cesium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, tungsten, molybdenum, gallium, indium, thallium, germanium, rhenium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, yttrium,
Common metals: such as iron, aluminum, copper, zinc and other metals: such as zirconium, hafnium, niobium, and tantalum;
1 light metal. Density less than 4500 kg / m³, such as aluminum, magnesium, potassium, sodium, calcium, titanium wire price strontium, and barium.
2. Heavy metals. Density greater than 4500 kg / m 3, such as copper, nickel, cobalt, lead, zinc, tin, antimony, bismuth, cadmium, mercury and the like.
3. Precious metals. Expensive than the commonly used metal prices, low crustal abundance, purification difficulties, such as gold, silver and platinum group metals.
4 non-metallic elements. Properties at between metal and nonmetal such as silicon, selenium, tellurium, arsenic, boron, and the like.
5 rare. Including rare light metals such as lithium, rubidium, cesium, etc.;
6 rare refractory metals such as titanium, zirconium, molybdenum, tungsten, etc.;
7 dispersed rare metals such as gallium, indium, germanium, and thallium;
8 rare earth metals, such as titanium pipe price scandium, yttrium, a lanthanide metal;
9. Radioactive metals, such as radium, francium, polonium and actinides uranium and thorium.
The ductility of the metal is preferably gold (Au), good electrical conductivity at room temperature followed by silver (Ag), copper (Cu), aluminum (Al) and the like;
Common metals: such as iron, aluminum, copper, zinc and other metals: such as zirconium, hafnium, niobium, and tantalum;
1 light metal. Density less than 4500 kg / m³, such as aluminum, magnesium, potassium, sodium, calcium, titanium wire price strontium, and barium.
2. Heavy metals. Density greater than 4500 kg / m 3, such as copper, nickel, cobalt, lead, zinc, tin, antimony, bismuth, cadmium, mercury and the like.
3. Precious metals. Expensive than the commonly used metal prices, low crustal abundance, purification difficulties, such as gold, silver and platinum group metals.
4 non-metallic elements. Properties at between metal and nonmetal such as silicon, selenium, tellurium, arsenic, boron, and the like.
5 rare. Including rare light metals such as lithium, rubidium, cesium, etc.;
6 rare refractory metals such as titanium, zirconium, molybdenum, tungsten, etc.;
7 dispersed rare metals such as gallium, indium, germanium, and thallium;
8 rare earth metals, such as titanium pipe price scandium, yttrium, a lanthanide metal;
9. Radioactive metals, such as radium, francium, polonium and actinides uranium and thorium.
The ductility of the metal is preferably gold (Au), good electrical conductivity at room temperature followed by silver (Ag), copper (Cu), aluminum (Al) and the like;
titanium bar Nitinol material can become earthquake
A length of about 10 seconds of test input on a flexible nitinol conducted , we found that protection may help bridge earthquake safety.
In this test , the new alloy buy titanium bar greatly reduces the extent of the damage a length of about 100 feet ( 30 meters ) of concrete bridge model. Scenario simulation is 1994 Los Angeles Northridge (Northridge) earthquake . . That quake killed 57 people and caused extensive damage in Los Angeles .\University of Nevada research team simulated a magnitude-8.0 quake and shake the bridge for 10 seconds. titanium wire price This time is sufficient in the Northridge earthquake razed bridges and flyovers .
Since the bridge has reinforced nitinol , so after a violent shaking , it still did not fall. Although the partial destruction of the concrete , but the overall infrastructure remains intact . .
Engineering professor M. Saiid Saiidi said nitinol flexible.
He told Reuters in a telephone interview , said : "This is a typical shape memory material ."
"They remember what they were before the earthquake looks like , they are often able to keep the prototype. They experienced the earthquake deformation , but soon they went back to the titanium plate suppliers previous appearance ."
In this test , the new alloy buy titanium bar greatly reduces the extent of the damage a length of about 100 feet ( 30 meters ) of concrete bridge model. Scenario simulation is 1994 Los Angeles Northridge (Northridge) earthquake . . That quake killed 57 people and caused extensive damage in Los Angeles .\University of Nevada research team simulated a magnitude-8.0 quake and shake the bridge for 10 seconds. titanium wire price This time is sufficient in the Northridge earthquake razed bridges and flyovers .
Since the bridge has reinforced nitinol , so after a violent shaking , it still did not fall. Although the partial destruction of the concrete , but the overall infrastructure remains intact . .
Engineering professor M. Saiid Saiidi said nitinol flexible.
He told Reuters in a telephone interview , said : "This is a typical shape memory material ."
"They remember what they were before the earthquake looks like , they are often able to keep the prototype. They experienced the earthquake deformation , but soon they went back to the titanium plate suppliers previous appearance ."
titanium axle Research Investment casting with
Research Investment casting with titanium oxide ceramic shell -shell technology for
Titanium Investment casting technology to meet the needs of the aerospace industry and developed , has been widely used in aerospace titanium titanium components and civilian material titanium structures manufacturing. Practice has proved that the titanium alloy precision casting technology has become almost no margin of several forming processes to obtain maximum effectiveness of a process [ 1-3] . With the extensive application of titanium castings , its increasingly stringent quality and usability requirements , in addition, the level of costs also limit its application prospects is an important indicator . Graphite was low cost but poor quality of the casting surface , and is not suitable for the production of thin-walled complex parts [ 4 ] , but with the surface layer of refractory metal or yttrium oxide surface layer ceramic shell can be cast out of high quality titanium castings, but the cost is very high [ 5,6 ] . For this study the low -cost , suitable for the production of complex thin-walled shell technology for a new type of titanium oxide ceramic Investment casting is .
1 Materials and experimental methods
1.1 The main system shell material
Mold material : the material properties of the selected mode is shown in Table 1. The main use of imported wax wax casting specifically for titanium , gate part is low cost, performance can meet the requirements of homemade wax , respectively, after pressing, welding titanium wire price synthetic wax module.
Table 1 titanium casting mold materials with properties
Table1 Waxes used for making shells
Performance of imported wax homemade wax
Dropping Point / ℃ 69 ~ 71 70.5
Freezing point / ℃ 58 ~ 59 60 ~ 62
Linear shrinkage / % 1.3 0.4 0.6
Penetration / 1/10mm 12 ~ 14 11
Zhao hardness 21.1 19
Tensile strength / MPa 3.69 2.91
Adhesive wetting angle / ° 89 ~ 92 79 ~ 82
Density / g/mm3 0.91 ~ 0.94 0.95 ~ 1
Ash / % < 0.01 0.05
The surface layer and the adjacent surface layer of slurry : The main components of zirconia refractories , size of 30μm or less. Organic zirconium sol as a binder , the size of the refractory rubber match should be 10 ~ 15nm.
The surface layer and the adjacent surface layer of sanding : the main component of the surface layer is made of zirconium dioxide sand , the size of 150 ~ 300μm. To reduce costs, the use of adjacent surface layer is mainly composed of ZrO2.SiO2 zircon sand . The results show that the diffusion of Si is not seen in the casting , it is feasible the use of zircon sand .
Back layer system shell material: silica sol as a binder , using Morley powder and sand as refractories.
1.2 system shell method
The order of addition batter titanium plate suppliers followed binders , refractory powder , trace additives. Minor amounts of additives to improve the stability of the coating role is to improve the wettability of the material and the mold , etc., and to prevent drying of the surface layer after the return water soluble additive is selected micro- organic material can be removed during the calcination . Stir batter than 2h at room temperature ( about 20 ℃) in the air , after the return of 1h to use .
O face the same batter pulp and raw materials , the production process is the same, only slightly smaller concentrations . Slurry feed back order binders , refractory powder. Also need to continuously stirred slurry back more than 2h , after the return of before use. Depending on the size of the backing layer casting , painted hanging normally takes 4-9 layers.
Drying : Drying time the surface layer and the adjacent surface layer are 24h, the temperature is 20 ℃, relative humidity of not less than 60% , the drying time of the backing layer is not less than 4h, the same as other conditions and the surface layer .
Dewaxing process : the use of microwave dewaxing , the equipment used for the large cavity size , 1500W Adjustable microwave intensity.
Roasting process : After dewaxing gas shell fired at without protection roaster .
Optimization of two main titanium rod for sale parameters of the Shell Technology
In all system shell process parameters on shell quality and ultimately a greater impact on the quality of castings are: batter ingredients, namely powder -liquid ratio , dewaxing and roasting process parameters [ 7 ] , this research labs now there are devices on the above parameters in-depth study and optimize selection.
Titanium Investment casting technology to meet the needs of the aerospace industry and developed , has been widely used in aerospace titanium titanium components and civilian material titanium structures manufacturing. Practice has proved that the titanium alloy precision casting technology has become almost no margin of several forming processes to obtain maximum effectiveness of a process [ 1-3] . With the extensive application of titanium castings , its increasingly stringent quality and usability requirements , in addition, the level of costs also limit its application prospects is an important indicator . Graphite was low cost but poor quality of the casting surface , and is not suitable for the production of thin-walled complex parts [ 4 ] , but with the surface layer of refractory metal or yttrium oxide surface layer ceramic shell can be cast out of high quality titanium castings, but the cost is very high [ 5,6 ] . For this study the low -cost , suitable for the production of complex thin-walled shell technology for a new type of titanium oxide ceramic Investment casting is .
1 Materials and experimental methods
1.1 The main system shell material
Mold material : the material properties of the selected mode is shown in Table 1. The main use of imported wax wax casting specifically for titanium , gate part is low cost, performance can meet the requirements of homemade wax , respectively, after pressing, welding titanium wire price synthetic wax module.
Table 1 titanium casting mold materials with properties
Table1 Waxes used for making shells
Performance of imported wax homemade wax
Dropping Point / ℃ 69 ~ 71 70.5
Freezing point / ℃ 58 ~ 59 60 ~ 62
Linear shrinkage / % 1.3 0.4 0.6
Penetration / 1/10mm 12 ~ 14 11
Zhao hardness 21.1 19
Tensile strength / MPa 3.69 2.91
Adhesive wetting angle / ° 89 ~ 92 79 ~ 82
Density / g/mm3 0.91 ~ 0.94 0.95 ~ 1
Ash / % < 0.01 0.05
The surface layer and the adjacent surface layer of slurry : The main components of zirconia refractories , size of 30μm or less. Organic zirconium sol as a binder , the size of the refractory rubber match should be 10 ~ 15nm.
The surface layer and the adjacent surface layer of sanding : the main component of the surface layer is made of zirconium dioxide sand , the size of 150 ~ 300μm. To reduce costs, the use of adjacent surface layer is mainly composed of ZrO2.SiO2 zircon sand . The results show that the diffusion of Si is not seen in the casting , it is feasible the use of zircon sand .
Back layer system shell material: silica sol as a binder , using Morley powder and sand as refractories.
1.2 system shell method
The order of addition batter titanium plate suppliers followed binders , refractory powder , trace additives. Minor amounts of additives to improve the stability of the coating role is to improve the wettability of the material and the mold , etc., and to prevent drying of the surface layer after the return water soluble additive is selected micro- organic material can be removed during the calcination . Stir batter than 2h at room temperature ( about 20 ℃) in the air , after the return of 1h to use .
O face the same batter pulp and raw materials , the production process is the same, only slightly smaller concentrations . Slurry feed back order binders , refractory powder. Also need to continuously stirred slurry back more than 2h , after the return of before use. Depending on the size of the backing layer casting , painted hanging normally takes 4-9 layers.
Drying : Drying time the surface layer and the adjacent surface layer are 24h, the temperature is 20 ℃, relative humidity of not less than 60% , the drying time of the backing layer is not less than 4h, the same as other conditions and the surface layer .
Dewaxing process : the use of microwave dewaxing , the equipment used for the large cavity size , 1500W Adjustable microwave intensity.
Roasting process : After dewaxing gas shell fired at without protection roaster .
Optimization of two main titanium rod for sale parameters of the Shell Technology
In all system shell process parameters on shell quality and ultimately a greater impact on the quality of castings are: batter ingredients, namely powder -liquid ratio , dewaxing and roasting process parameters [ 7 ] , this research labs now there are devices on the above parameters in-depth study and optimize selection.
titanium axle powder -liquid ratio across the layer
2.1 powder -liquid ratio across the layer of coating thickness and suspension rate impact
Table 2 powder-liquid ratio on the opposite layer coating thickness and coating suspension rates . The results show that the greater the surface pulp powder -liquid ratio , the greater the thickness of the surface coating , the coating suspension , the better. Generally believed that if the surface coating is too thin (<0.2mm), the shell will be affected by sanding the surface , the roughness increased. If the coating is material titanium too thick (> 0.6mm), the coating , poor mobility, easy accumulation , during the drying or firing cracks easily [ 7 ] , which in this study has also been confirmed in the present study therefore the powder in the liquid ratio should be controlled between 5.0:1 - 6.0:1 .
Table 2 in the powder -liquid ratio of coating performance
Table2 Effects of solid / liquid ratios on the properties of coating
4.0:1 5.0:1 5.5:1 powder -liquid ratio 6.0:1
Coating thickness / mm 0.11 0.25 0.36 0.65
Coating suspension rate / % 88.3 90.1 93.1 97.6
2.2 Effect of shell powder -liquid ratio and calcination temperature on the room temperature and high residual strength
Figure 1 shows the ratio of powder and liquid at room temperature and high temperature effect on residual strength . Strength of the sample is composed of five levels of plasma and surface sand composition , each drying 24h, continuous coating hanging , firing 4h. Flexural strength of the strength test .
Figure 1 powder-liquid ratio of the residual strength of the opposite layer
Fig.1 Effects of S / L ratios on the remain flexural of
surface coats baked at different temperatures
The results showed that the powder -liquid ratio improved shell specimen bending strength . Calcination temperature is increased , the flexural strength increases with . Since 1100 ℃ ZrO2 occurs near the phase transition , so that the strength in the vicinity of this temperature increase is not significant , but the phase change process , the lattice of unstable energy increased activity increased , so should be avoided in the actual production of the calcined temperature. After calcination at 1200 ℃ by titanium wire price the high ratio of powder and liquid coatings ( 6.5:1 ) intensity decreased slightly reason: Because the coating is too thick , a slight increase in the calcination process of internal defects , thereby affecting its strength. From the results in Table 2 and Figure 1 show that the optimum value of 5.5:1 powder-liquid ratio of the surface layer material . The firing temperature is preferably at about 1200 ℃, but for small pieces of calcination temperature can be set at around 1000 ~ 1050 ℃.
2.3 Optimization of process parameters dewaxing
For this study cast casting spade 150mm × 100mm , thickness of 2.5mm, the microwave dewaxing process, the time relationship between the intensity of the microwave shown in Figure 2 and dewaxing .
Figure 2 microwave intensity and dewaxing time
(a) the inner surface intact ; (b) inner surface microcracks
Fig.2 Effects of different titanium rod for sale microwave intensities on dewaxing time
(a) no crack; (b) have cracks
Figure in a district that is less than 70% when the microwave intensity , dewaxed shell inner surface smooth , with little residual wax, no visible cracks. When the microwave intensity is too large (b zone ) , dewaxed shell intact , although overall , but there are a few cracks in the surface layer , with the microwave intensity increased the number of cracks increases , the reasons for this phenomenon may be due to over- heating rate fast , since the internal stress of the inner and outer layers of different thermal expansion coefficients of the time to produce slack . Therefore microwave intensity used in this study was 50% , dewaxing time about 8min. Through other experiments show that this dewaxing process useful in the present titanium rod stock study not only the spade member is equally applicable to other shapes and sizes of parts.
Table 2 powder-liquid ratio on the opposite layer coating thickness and coating suspension rates . The results show that the greater the surface pulp powder -liquid ratio , the greater the thickness of the surface coating , the coating suspension , the better. Generally believed that if the surface coating is too thin (<0.2mm), the shell will be affected by sanding the surface , the roughness increased. If the coating is material titanium too thick (> 0.6mm), the coating , poor mobility, easy accumulation , during the drying or firing cracks easily [ 7 ] , which in this study has also been confirmed in the present study therefore the powder in the liquid ratio should be controlled between 5.0:1 - 6.0:1 .
Table 2 in the powder -liquid ratio of coating performance
Table2 Effects of solid / liquid ratios on the properties of coating
4.0:1 5.0:1 5.5:1 powder -liquid ratio 6.0:1
Coating thickness / mm 0.11 0.25 0.36 0.65
Coating suspension rate / % 88.3 90.1 93.1 97.6
2.2 Effect of shell powder -liquid ratio and calcination temperature on the room temperature and high residual strength
Figure 1 shows the ratio of powder and liquid at room temperature and high temperature effect on residual strength . Strength of the sample is composed of five levels of plasma and surface sand composition , each drying 24h, continuous coating hanging , firing 4h. Flexural strength of the strength test .
Figure 1 powder-liquid ratio of the residual strength of the opposite layer
Fig.1 Effects of S / L ratios on the remain flexural of
surface coats baked at different temperatures
The results showed that the powder -liquid ratio improved shell specimen bending strength . Calcination temperature is increased , the flexural strength increases with . Since 1100 ℃ ZrO2 occurs near the phase transition , so that the strength in the vicinity of this temperature increase is not significant , but the phase change process , the lattice of unstable energy increased activity increased , so should be avoided in the actual production of the calcined temperature. After calcination at 1200 ℃ by titanium wire price the high ratio of powder and liquid coatings ( 6.5:1 ) intensity decreased slightly reason: Because the coating is too thick , a slight increase in the calcination process of internal defects , thereby affecting its strength. From the results in Table 2 and Figure 1 show that the optimum value of 5.5:1 powder-liquid ratio of the surface layer material . The firing temperature is preferably at about 1200 ℃, but for small pieces of calcination temperature can be set at around 1000 ~ 1050 ℃.
2.3 Optimization of process parameters dewaxing
For this study cast casting spade 150mm × 100mm , thickness of 2.5mm, the microwave dewaxing process, the time relationship between the intensity of the microwave shown in Figure 2 and dewaxing .
Figure 2 microwave intensity and dewaxing time
(a) the inner surface intact ; (b) inner surface microcracks
Fig.2 Effects of different titanium rod for sale microwave intensities on dewaxing time
(a) no crack; (b) have cracks
Figure in a district that is less than 70% when the microwave intensity , dewaxed shell inner surface smooth , with little residual wax, no visible cracks. When the microwave intensity is too large (b zone ) , dewaxed shell intact , although overall , but there are a few cracks in the surface layer , with the microwave intensity increased the number of cracks increases , the reasons for this phenomenon may be due to over- heating rate fast , since the internal stress of the inner and outer layers of different thermal expansion coefficients of the time to produce slack . Therefore microwave intensity used in this study was 50% , dewaxing time about 8min. Through other experiments show that this dewaxing process useful in the present titanium rod stock study not only the spade member is equally applicable to other shapes and sizes of parts.
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