摘要
采用放电等离子烧结技术(SPS)制备含有不同TiC质量分数的硬质合金,揭示材料的显微结构对其硬度和磨损行为的影响机理,探索高TiC质量分数硬质合金作为耐磨材料的可能性。结果表明:SPS烧结可以得到组织致密的样品,TiC质量分数为55%的硬质合金孔隙率为0.07%,随着TiC质量分数的增加,硬质合金的孔隙率也随之上升,当TiC质量分数为70%时,孔隙率为0.21%。在烧结过程中,Mo在TiC颗粒周围参与形成复杂的核壳结构,Ni分布于金属粘结相中。大尺寸TiC颗粒保持原始形貌,小尺寸TiC颗粒逐渐球化,并出现颗粒富集区。硬质合金的硬度随TiC质量分数的增加而增加,TiC质量分数70%的硬质合金的显微硬度(HV)相较于TiC质量分数55%的增加559。通过摩擦磨损试验发现,TiC颗粒受到应力出现破碎与剥落,TiC质量分数55%硬质合金的磨损率最高,耐磨性最差。TiC质量分数70%硬质合金的磨损率最低,耐磨性最好。
Cemented carbides with different TiC mass fractions were prepared by spark plasma sintering(SPS) to reveal the influence mechanism of microstructure on hardness and wear behavior, and to explore the possibility of cemented carbides with high TiC mass fraction as wear-resistant materials.The results show that the sample with compact microstructure can be obtained by SPS sintering. The porosity of cemented carbide with 55% TiC mass fraction is 0.07%, and the porosity of cemented carbide increases with the increase of TiC mass fraction. In the sintering process, Mo participates in the formation of complex core-shell structure around TiC particles, and Ni distributes in the metal bonded phase. The large size TiC particles keeps their original morphology, while the small size TiC particles spheroidizes gradually and the particle enrichment area appears. The hardness of cemented carbide increases with the increase of TiC mass fraction. The microhardness(HV) of cemented carbide with 70%TiC mass fraction is 559 higher than that with 55% TiC mass fraction. The friction and wear tests show that the TiC particles are broken and spalling under stress, and the cemented carbide with 55% TiC mass fraction has the highest wear rate and the worst wear resistance. The cemented carbide with 70% TiC mass fraction has the lowest wear rate and the best wear resistance.
作者
张怀举
王帅
郑开宏
罗铁钢
Zhang Huaiju;Wang Shuai;Zheng Kaihong;Luo Tiegang(School of Materials Science and Engineering,Lanzhou Jiaotong University,Lanzhou 730070,Gansu,China;Insti-tute of New Materials,Guangdong Academy of Sciences,National Engineering Research Center of Powder Metallurgy of Titanium&Rare Metals,Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application,Guangzhou 510650,Guangdong,China;Guangdong Province Engineering Research Center of Steel Matrix Compos-ites,Guangzhou 510650,Guangdong,China)
出处
《钢铁钒钛》
CAS
北大核心
2022年第5期75-80,共6页
Iron Steel Vanadium Titanium
基金
国家重点研发计划(2021YFB3701204)
广东省重点研发计划项目(2019B010942001)
广东省科学院发展专项资金项目(2022GDASZH-2022010103)
广东省科技专项资金项目(江门)-江科[2020]182号。
