SPS熔铸工艺制备Nb/Nb5Si3原位复合材料

Fabrication of Nb/Nb5Si3 in-situ Composites by SPS-Casting Technology

摘要:

以Nb，Si粉末为原料，采用放电等离子烧结(SPS)技术，原位合成了密实的Nb/Nb5Si3复合材料。利用扫描电镜(SEM)、电子探针微区分析(EPMA)和X射线衍射(XRD)等手段对材料的组织结构进行了分析，并探讨了材料的结构形成机制。结果表明，合成的材料由近球状的Nb颗粒与Nb-Nb5Si3共晶组织组成；SPS过程中产生的放电等离子体使Si粉及Nb颗粒的表面熔化，熔融的Nb和Si在冷却过程中发生共晶反应而形成Nb-Nb5Si3共晶体，而未反应完的Nb颗粒则均匀分布在共晶组织中

Abstract:

With Nb and Si powders as starting material, the dense Nb/Nb5Si3 composites were in situ synthesized by spark plasma sintering (SPS) technology. The microstructures of the composites were analyzed through SEM, XRD and EPMA, and the forming mechanism was studied. The results show that the synthesized composites consist of nearly-spherical Nb particles and Nb-Nb5Si3 eutectic. Si powders and surface of Nb particles were melted due to the action of spark plasma during SPS, and the Nb-Nb5Si3 eutectic was formed by eutectic reaction of melted Si and Nb during cooling process. The residual particles of Nb were distributed homogeneously in the eutectic microstructure