用热压法低温快速制备微-纳米Al_2O_3原位增强Fe-Cr-Ni

Fast Fabrication of In-Situ Micro-Nano Al_2O_3 Reinforced Fe-Cr-Ni Composites by Hot-Pressing at Low Temperature

采用低温快速热压法原位反应制备了微-纳米Al_2O_3原位增强Fe-Cr-Ni金属基复合材料。研究了烧结温度和保温时间对复合材料微观组织和力学性能的影响。XRD分析表明在烧结温度为700℃和800℃时,生成产物为(fcc)Cr_(0.19)Fe_(0.7)Ni_(0.11),(fcc)Fe-Cr和Al_2O_3;SEM分析显示烧结温度为800℃,保温时间为1h时晶粒分布更均匀,形成更致密的网状结构并且断裂形式为穿晶断裂和沿晶断裂;TEM分析得出微-纳米Al_2O_3颗粒为晶间型和晶内型复合。通过调节烧结温度和保温时间,制备了力学性能优良的微-纳米Al_2O_3原位增强Fe-Cr-Ni金属基复合材料。

In-situ micro-nano Al2O3 reinforced Fe-Cr-Ni heat-resistant metal matrix composites were fabricated rapidly by hot-pressing at low temperature. The influence of temperature and holding time on microstructures and mechanical properties was investigated. XRD showed that the composites were comprised predominantly of （fcc） Cr0.19Fe0.7Ni0.11, （fcc） Fe-Cr and alumina at 700 ℃ and 800 ℃. SEM analysis indicated that distribution of grain was uniform and compacted network was formed. The fracture of the composites occurred in transgranular and intergranular. TEM analysis revealed the distribution of the micro-nano Al2O3 particles in combination of the intra-type and inter-type. The in-situ generated micro-nano Al2O3 reinforced Fe-Cr-Ni heat-resistant metal matrix composites with good mechanical properties were obtained through adjusting the sintering temperature and the holding time.