多孔TiC/NiAl复合材料的孔洞形貌及抗压强度

Pore morphologies and compressive strength of TiC/NiAl porous composites

通过控制Ti、C、Ni、Al粉末之间的反应,利用自蔓延技术原位合成多孔TiC/NiAl复合材料,研究Ti-C(摩尔比1∶1)含量对多孔材料孔洞形貌和抗压强度的影响。结果表明:多孔材料孔洞形貌主要受反应物吸附气体挥发和液相流动的影响,Ti-C含量增加,孔隙率和孔径增大。当Ti-C含量为0~25%时,孔洞分布均匀,形貌以近球形为主,孔径大小在20~70μm之间;多孔材料抗压强度随Ti-C含量增加逐渐增大。当Ti-C含量为30%时,除近球形孔洞外,还出现了一些尺寸大于100μm的形状不规则孔洞和狭长形孔洞,抗压强度下降。

TiC/NiAl porous composites were synthesized in situ by self-propagating technology through controlling the reaction among Ti,C,Ni and Al powers. Influences of Ti-C contents( molar ratio 1∶1) on the pore morphologies and compressive strength of the porous materials were investigated. The results show that the pore morphology of the porous materials is mainly affected by the volatilization of adsorbed gases and the flow of liquid phase,the porosity and pore size increase with the increase of Ti-C content. When Ti-C content is 0-25%,the distribution of pores with near spherical morphology is uniform,and the pore size ranges between 20-70 μm,the compressive strength of the porous material increases with the increase of Ti-C content. When Ti-C content is 30%,besides the near spherical pores,some irregular and long narrow pores larger than 100 μm are formed,and the compressive strength decreases.