稀土金属对超细晶WC-Co硬质合金组织和性能的影响

Effect of Rare Earth Metals on Properties of Ultrafine Grained WC-Co Cemented Carbide

以超细WC粉、Co粉作为主要原料,以稀土金属La、Sm、Y等作为添加剂,采用低压烧结法制备超细晶WC-Co硬质合金,研究了稀土对硬质合金显微组织结构与性能的影响。检测分析结果表明:稀土的添加对硬质合金组织结构无明显影响,合金组织较为致密;添加0.1%(质量分数,下同)含量的稀土La、Sm对硬质合金强度无提升作用,但对合金的矫顽磁力与硬度有一定的提升作用;添加稀土Y对硬质合金矫顽磁力、硬度与抗弯强度均有提升作用,添加0.3%含量稀土Y的硬质合金力学性能最高,硬度为1980 HV3,强度为4126 MPa。

Ultrafine grained cemented carbide was prepared by low pressure sintering with main raw materials of ultrafine WC powder and Co powder and additives of rare earth metals La,Sm,Y.The effects of rare earth on the microstructure and properties of cemented carbide were studied.The results show that the addition of rare earth has no obvious effect on the structure of cemented carbide,and the microstructure of cemented carbide is compact.The addition of 0.1%rare earth La and Sm has no positive effect on the bending strength of cemented carbide,but has a certain effect on the coercive force and hardness of cemented carbide.The addition of rare earth Y has a positive effect on the coercive force,hardness and strength of cemented carbide,and when the addition is 0.3%Y,the cemented carbide has the highest mechanical properties,of which the hardness is 1980 HV3 and the bending strength is 4126 MPa.