合金元素Cr对钛合金燃烧行为的影响

Effect of Alloying Element,Cr,on the Burning Behavior of Titanium Alloys

以直流电弧激发燃烧法（ＤＣＳＢ）点燃钛合金，探讨了合金元素Ｃｒ对钛合金燃烧行为的影响。结果表明：合金元素Ｃｒ含量高于１０％可改善钛合金的阻燃性能，大于１５％效果更明显，而ＴｉＣｒ二元合金不具有阻燃性能。原因在于：ＴｉＣｒ合金燃烧产物表面均开裂多孔，Ｔｉ（＜１０％）Ｃｒ合金的燃烧产物与基体的界面亦如此，不可能阻止氧向基体内扩散；而Ｔｉ（＞１０％）Ｃｒ合金的燃烧产物与基体的界面富积Ｃｒ，氧化物比较致密，可阻止氧向基体内扩散，降低燃烧速度。ＴｉＣｒ合金的燃烧产物是ＴｉＯ２，ＴｉＯ和ＴｉＣｒＯ３。

The alloys Ti 35V 15Cr(c) and Ti 25V 15Cr 02Si(Ti40) exhibit good burn resistance,however,the influence of the alloying element,Cr,on alloy burning behavior is not clear.Effect of alloying element,Cr,on titanium alloy burning behavior is studied by means of the direct current simulation burn(DCSB) ignition method.The results indicate that the burn resistance is improved as the Cr content is increased beyond 10%,even more so beyond 15%.However,Ti Cr binary alloys do not reveal burn resistant behavior.The reason is that the burned Ti Cr alloy surface is porous and cracked,and the interface between burned product and the matrix is the same as it is when the Cr content is less than 10%,which is insufficient to retard oxygen diffusion into the matrix.But the interface of Ti (>10)Cr alloys is rich in Cr,and the oxide film is tenacious and able to retard oxygen diffusion into the matrix thereby decreasing the burning velocity.The burned products of Ti Cr alloys are TiO\-2,TiO and TiCrO\-3.