等离子烧结工艺对WC/Cr_(3)C_(2)/La_(2)O_(3)刀具材料力学性能的影响  

Effect of plasma sintering process on the mechanical properties of WC/Cr_(3)C_(2)/La_(2)O_(3)cutting tool materials

作　　者：钟韬 郭荣臻 林晓川 柳龙婷 王佳鑫 徐志强 郭世柏 ZHONG Tao;GUO Rongzhen;LIN Xiaochuang;LIU Longting;WANG Jiaxin;XU Zhiqiang;GUO Shibo(School of Materials Science and Engineering,Hunan University of Science and Technology,Xiangtan 411201,China)

机构地区：[1]湖南科技大学材料科学与工程学院,湘潭411201

出　　处：《粉末冶金技术》2024年第6期582-588,共7页Powder Metallurgy Technology

基　　金：湖南省教育厅重点资助项目(23A0379);湖南省大学生创新创业一般项目(S202310534108);中国大学生创新创业项目(S202310534003S);湖南省教研教改一般项目(HNJG-2021-0643)。

摘　　要：针对传统硬质合金刀具高速切削过程中粘结相易于磨损等问题,采用放电等离子烧结制备了WC/Cr_(3)C_(2)/La_(2)O_(3)刀具材料,研究了Cr_(3)C_(2)添加量(质量分数,0%~2.00%)和工艺参数(烧结温度1500~1700℃,烧结压力15~45 MPa)对刀具材料微观组织和力学性能的影响。结果表明,添加质量分数0.50%的Cr_(3)C_(2)并在1550℃和25 MPa条件下烧结,得到的WC/Cr_(3)C_(2)/La_(2)O_(3)刀具材料相对密度、抗弯强度和硬度分别为97.5%、1281.0 MPa和HV 2124.3。随着烧结温度增加,材料的相对密度增加,微观组织逐渐均匀;但过高温度会导致晶粒异常长大,组织分布不均,孔隙增多,综合力学性能下降。随着烧结压力增加,材料晶粒细小,组织更加均匀,力学性能增加;但当压力超过25 MPa后,材料力学性能有所下降。To solve the problem of adhesive phase wear for the traditional cemented carbide tools in the high-speed cutting process,the WC/Cr_(3)C_(2)/La_(2)O_(3)tool materials were prepared by spark plasma sintering(SPS).The effects of Cr_(3)C_(2)addition amount(mass fraction,0%~2.00%)and process parameters(sintering temperature 1500~1700℃and sintering pressure 15~45 MPa)on the microstructure and mechanical properties of the tool materials were studied.The results show that,the optimum Cr_(3)C_(2)content is 0.50%,and the WC/Cr_(3)C_(2)/La_(2)O_(3)cemented carbide sintered at 1550℃and 25 MPa has the best comprehensive properties as the relative density,bending strength,and Vickers hardness are 97.5%,1281.0 MPa,and HV 2124.3,respectively.With the increase of sintering temperature,the relative density increases and the microstructure becomes more even for the WC-based tool materials.However,too high temperature leads to the abnormal growth of grains,the uneven distribution of microstructure,more porosity,and the lower mechanical properties.As the sintering pressure increases,the grain size reduces,the microstructure becomes more even,and the mechanical properties increase.While the sintering pressure is above 25 MPa,the mechanical properties of tool materials decrease.

关 键 词：硬质合金 刀具材料 放电等离子烧结 微观组织 力学性能 

分 类 号：TF125[冶金工程—粉末冶金] TG146.4[冶金工程—冶金物理化学]