TiCN_(p)增强高铬铸铁复合材料的制备与性能  

Preparation and Properties of TiCN_(p)Reinforced High Chromium Cast Iron Composites

作　　者：赵吉康 肖平安[1] 顾景洪 钟斯远 ZHAO Jikang;XIAO Ping’an;GU Jinghong;ZHONG Siyuan(School of Materials Science and Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学材料科学与工程学院,长沙410082

出　　处：《材料导报》2023年第13期191-195,共5页Materials Reports

基　　金：国家自然科学基金(51574449)。

摘　　要：本工作以TiCN_(p)和20Cr高铬铸铁粉末为原料,采用压制和超固相液相烧结(SLPS)工艺,制备含10%~30%(质量分数,下同)TiCN_(p)的高铬铸铁复合材料,系统研究了增强相含量和烧结温度对复合材料致密化行为、显微组织、物相组成和力学性能的影响规律。研究结果表明,通过真空液相烧结可以制备出相对致密度均达到97.5%以上的各成分复合材料,物相主要由TiCN、Cr_(7)C_(3)碳化物、马氏体和少量奥氏体组成;随着增强相添加量逐步增加,TiCN_(p)沿晶界分布,逐渐形成网状分布结构,而Cr_(7)C_(3)越来越多地在烧结过程中没有熔化的合金基体中析出和粗化;这使得复合材料的硬度线性上升,而抗弯强度和冲击韧性则降低。当TiCN_(p)添加量为30%时复合材料的力学性能可以达到硬度87.8HRA,抗弯强度1304 MPa,冲击韧性2.35 J/cm^(2)。Taking TiCN_(p)and 20Cr high chromium cast iron powder as raw materials,reinforced high chromium cast iron with 10wt%—30wt%TiCN_(p)in this work was fabricated by supersolidus liquid phase sintering(SLPS)method.The influence of TiCN_(p)addition amount and sintering temperature on its densification,constituent phase,microstructure and mechanical properties have been investigated systematically.The results show that the relative density of the TiCN_(p)sintered through SLPS technique could reach to 97.5%,and it’s phase composition containing TiCN,Cr_(7)C_(3) carbides,martensite and a small amount of austenite.Besides,with the increment of TiCN_(p)addition amount,TiCN_(p)gradually forming a net distribution along the grain boundary.Meanwhile,more and more Cr_(7)C_(3) carbides were precipitated and coarsened in the unmelted alloy matrix,which could lead to the linearly increment of the hardness of the TiCN P but decreases their bending strength and impact toughness.And in general it is worth noting that the sintered composite with 30wt%TiCN_(p)has great mechanical properties with hardness of 87.8HRA,bending strength of 1304 MPa and impact toughness of 2.35 J/cm^(2).

关 键 词：复合材料 TiCN_(p) PM高铬铸铁 力学性能 显微组织 

分 类 号：TB331[一般工业技术—材料科学与工程]