Ti-Al基微孔材料的自蔓延高温合成

Research on SHS Ti-Al based porous material

以Al,Ti,Fe等为主要原料 ,采用SHS法研制了Ti Al基微孔过滤材料 ;研究了原材料和生成相对材料的孔隙率、透气系数、孔隙形状及大小的影响 ;分析了热爆与成孔机理并根据马尔科夫状态转移原理建立了热爆反应模型。结果表明 :材料的孔隙率、透气系数随原料Fe含量的增加而提高 ,当Fe含量为 5 0 %时 ,材料的孔隙率为5 4% ,透气系数为 6 86 4.2Pa·min-1;孔隙的形状和大小取决于原料Al和生成物FeAl的分布和大小 ;热爆过程是先Fe Al热爆 ,然后引爆Ti Al;孔隙是由于低熔点的Al和FeAl在热爆过程中的熔化、冲刷而形成的 ;利用马尔科夫状态转移原理可以建立热爆反应模型 ,进而可以预测热爆反应的起始时间。

Ti Al based porous material was investigated through SHS process of Al, Ti, Fe. The influences of raw materials and phases on the porosity, gas permeability, pore size and shape were studied. The mechanism of thermal explosion and pore formation was analyzed. The thermal explosion model was established on the basis of Markov. The results show that the porosity and gas permeability of material are enhanced with the rise of the Fe content, at 50% Fe, porosity is 54%, gas permeability 6?864.2?Pa·min -1 ; the shape and size of pore is related to the distribution and size of Al and FeAl; the thermal explosion is achieved by Fe Al thermal explosion, inducing Ti Al thermal explosion; the formation of pore is accomplished with melting, scouring of Al and FeAl; the thermal explosion model can be established on the basis of Markov, and by means of it , the time of thermal explosion can be predicted.