碳含量对WC-6%Ni细晶硬质合金组织结构及性能的影响

Influence of Carbon Content on Microstructure and Properties of WC-6%Ni Cemented Carbide

本文通过配制WC碳含量在6.00%至6.15%范围的WC-6%Ni细晶硬质合金,采用光学金相、X射线衍射、SEM等分析方法,对比研究了不同碳含量对WC-6%Ni细晶硬质合金组织结构及性能的影响。结果表明:WC碳含量为6.00%时,合金出现脱碳现象;在两相区范围内,随着WC碳含量的增加,合金出现晶粒长大现象,且粗大晶粒数量逐渐增多;合金硬度和密度随WC碳含量的增加逐渐降低;随着WC碳含量的增加,合金的抗弯强度呈现出先升高然后降低的趋势,并在WC碳含量为6.09%时出现最大值(2 360 MPa);合金断裂韧性随WC碳含量的增加而增加。

In this paper, WC-6%Ni fine cemented carbide with WC carbon content range of 6.00% to 6.15% were prepared, and the microstrueture and properties were observed and tested using optical microscope, X-ray diffraction, SEM, etc. The results show that decarburization would be found in WC-6%Ni cemented carbide when the carbon content is 6.00%. In the two phase region, with the increasing of carbon content, alloys appear coarse grain and the number of coarse grain gradually increases. With the increase of carbon content, the hardness and density values decrease gradually, while the fracture toughness increases. The bending strength increases firstly and then decreases with carbon content increasing. When the carbon content is 6.09%, the bending strength appears the maximum value of 2 360 MPa.