激光烧结时间对TiC-WC-Mo_2C-Ni系金属陶瓷显微组织和抗弯强度的影响  

Effects of Laser Sintering Time on Microstructure and Transverse Strength of TiC-WC-Mo_2C-Ni Cermets

作　　者：韩成良[1] 谢劲松[1] 阳杰[1] 徐泽忠[1] 张凌云[1] 

机构地区：[1]合肥学院化学与材料工程系,安徽合肥230601

出　　处：《硬质合金》2016年第2期108-112,共5页Cemented Carbides

基　　金：安徽省高校优秀青年人才资助项目(gxyq ZD2016271;gxyq ZD2016272);安徽省高等学校自然科学基金资助项目(KJ2015A170;KJ2015B1105906);安徽省质量工程资助项目(2015ckjh081)

摘　　要：以TiC、WC、Mo_2C和Ni粉体为主要原料,采用传统制粉成形工艺和激光烧结技术成功制备出了TiC-Ni系金属陶瓷,研究了激光烧结时间对TiC-Ni系金属陶瓷显微组织和抗弯强度的影响。利用X-衍射和扫描电镜等手段对所制备的金属陶瓷的物相、显微组织、断口形貌和抗弯强度进行分析。结果表明：烧结时间在0.5~1 h内,获得的金属陶瓷物相较纯,当烧结时间超过1.5 h后,产物中出现了杂相。扫描电镜观察表明,随着烧结时间的延长,TiC、WC和Mo_2C相将逐渐消失,并通过溶解-再析出方式形成了（Ti,W,Mo）C完全固溶体。金属陶瓷的相对致密度和抗弯强度均随烧结时间的延长呈先增加后降低的规律。当烧结时间为1 h左右时,获得的金属陶瓷的相对致密度和抗弯强度分别约为99%和1 785 MPa,其断裂模式以沿晶断裂为主。TiC-WC-MozC-Ni cermets were prepared using TiC, WC, Mo2C and Ni powders as raw materials by traditional powder metallurgy technique combined with laser sintering （LS）. The effects of laser sintering time on microstructure and transverse strength of the cermets were studied. The as-sintered cermets were analyzed by means of XRD and SEM. The results show that the pure phase is obtained when the sintering tinle is between 1 and 1.5 hours. However, some impurity phases are found when the sintering time exceeds 1.5 hours. SEM observations indicate that the TiC, WC and MozC phases will disappear with the increase of sintering time and transform into a complete （Ti,W,Mo）C solid solution through a dissolution and precipitation process. The densitys and transverse strength of the as-prepared eermets increase first and then decrease with the increase of sintering time. The values of the relative density and transverse strength of the as-prepared cermets sintered in an hour are about 99% and 1 785 MPa, respectively. The main fracture model of the cermets with higher strength is transgranular fracture.

关 键 词：TiC-Ni系金属陶瓷 激光烧结 显微组织 抗弯强度 

分 类 号：TF124.5[冶金工程—粉末冶金]