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 .
没有评论:
发表评论