Ni含量对WC-Co-Ni硬质合金的力学性能和耐腐蚀性能的影响  

Effect of Ni Content on Mechanical Properties and Corrosion Resistance of WC-Co-Ni Cemented Carbides

作　　者：孙化鑫 徐淑波[1] 李辉 郑君姿 卢庆亮 SUN Hua-xin;XU Shu-bo;LI Hui;ZHENG Jun-zi;LU Qing-liang(School of Materials Science and Engineering,Shandong Jianzhu University,Jinan 250101,China;Jinan Metallurgical Research Institute Co.,Ltd.,Jinan 250022,China;Jinan Heavy Industry Group Co.,Ltd.,Jinan 250109,China)

机构地区：[1]山东建筑大学材料科学与工程学院,山东济南250101 [2]济南市冶金科学研究所有限责任公司,山东济南250022 [3]济南重工集团有限公司,山东济南250109

出　　处：《稀有金属与硬质合金》2022年第6期77-82,共6页Rare Metals and Cemented Carbides

基　　金：国家自然科学基金项目(41305124);山东省自然科学基金项目(ZR2021ME182)。

摘　　要：以WC、Co和Ni为原料,采用粉末冶金法制备不同镍钴比的硬质合金试样,研究了试样的微观组织,分析了试样的硬度、耐磨系数、抗弯强度和断裂韧性等力学性能,并通过电化学实验探究其耐腐蚀性能。结果表明,随着Ni含量的增加,WC-Co-Ni硬质合金的硬度、耐磨系数及抗弯强度均持续降低,断裂韧性先增加后降低。成分为WC-10%Co、WC-9%Co-1%Ni和WC-7%Co-3%Ni的三组试样的微观晶粒组织较为均匀细小,而其余试样微观晶粒组织粗大。通过在pH=7的3.5%NaCl溶液中的电化学实验可知,随着Ni含量的增加,WC-Co-Ni硬质合金试样的耐腐蚀性能增强。WC-7%Co-3%Ni合金试样的综合力学性能最佳,同时考虑到试样的耐腐蚀性能,优化配方后的合金可以更好地提高盾构刀具的工作寿命。WC,Co and Ni were used as raw materials to prepare cemented carbide samples with different nickel-cobalt ratios by powder metallurgy.The microstructure of the samples was studied, their mechanical properties, including hardness, wear resistance coefficient, bending strength, and fracture toughness were analyzed, and their corrosion resistance was studied through electrochemical experiments.The results show that with the increase of Ni content, the hardness, wear resistance coefficient and bending strength of WC-Co-Ni cemented carbides continue to decrease, while the fracture toughness increases at first and then decreases.The micro-grain structure of the three groups of samples with WC-10%Co, WC-9%Co-1%Ni and WC-7%Co-3%Ni is relatively fine and uniform while that of the remaining samples is coarse.The results of the electrochemical experiments in 3.5% NaCl solution with pH value of 7 show that the corrosion resistance of WC-Co-Ni cemented carbides increases with the increase of Ni content, and the WC-7%Co-3%Ni sample has the best comprehensive mechanical properties.Considering the corrosion resistan-ce of the sample, the optimized cemented carbides can better improve the working life of the shield tools.

关 键 词：粉末冶金 WC-Co-Ni硬质合金 力学性能 电化学腐蚀 Ni含量 

分 类 号：TG135.5[一般工业技术—材料科学与工程]