钴镍比对WC-14%(Co,Ni)硬质合金力学性能和在中性NaCl溶液中耐腐蚀性能的影响  

Effect of w(Co)/w(Ni)Ratio on Mechanical Properties and Corrosion Resistance of WC-14%(Co,Ni)Cemented Carbide in Neutral NaCl Solution

作　　者：赵玉玲[1,2] 张颢[1,2] 邹德良[2] 魏修宇[1,2] 金鹏[1,2] 崔焱茗[1,2] Zhao Yuling;Zhang Hao;Zou Deliang;Wei Xiuyu;Jin Peng;Cui Yanming(State Key Laboratory of Cemented Carbide,Zhuzhou Hunan 412000,China;Zhuzhou Cemented Carbide Croup Co.,Ltd.,Zhuzhou Hunan 412000,China)

机构地区：[1]硬质合金国家重点实验室,湖南株洲412000 [2]株洲硬质合金集团有限公司,湖南株洲412000

出　　处：《硬质合金》2021年第4期236-243,共8页Cemented Carbides

基　　金：湖南省创新型省份建设专项《超级地下工程智能成套装备关键技术研究与应用》(2019GK1010)。

摘　　要：本文以WC、Co及Ni粉为原料,采用传统粉末冶金方法制备了4种不同Co、Ni粘结相比例的WC-14%(Co,Ni)硬质合金样品,通过对比硬度、抗弯强度、断裂韧性、电化学极化曲线及浸泡实验结果,并利用扫描电镜、能谱分析等,研究了4种合金的力学性能及其在3.61%NaC(l pH=7)模拟海水溶液中的腐蚀行为。结果表明:随着w(Co)/w(Ni)比例的降低,合金的硬度和断裂韧性降低、抗弯强度则呈现先小幅增加后降低的趋势,当w(Co)︰w(Ni)=5︰5时,合金的硬度、抗弯强度和断裂韧性急剧下降;随着w(Co)/w(Ni)比例的降低,合金在NaCl模拟海水溶液中的自腐蚀电位升高,腐蚀电流密度降低,耐腐蚀性能增强;当w(Co)︰w(Ni)=7︰3时,即WC-9.8%Co-4.2%Ni合金的综合性能最佳,其力学性能和耐腐蚀性能的协同作用将有益于合金的使用寿命。In this paper,WC-14%(Co,Ni)cemented carbide with four different Co and Ni binder ratios were prepared by traditional powder metallurgy method using WC,Co and Ni powders as raw materials.The mechanical properties and corrosion behavior of the four alloys in 3.61%NaCl(pH=7)simulated seawater solution were studied by comparing hardness,bending strength,fracture toughness,electrochemical polarization curves and immersion test results,combined with scanning electron microscopy and energy dispersive spectrometry.The results show that with the decrease of w(Co)/w(Ni)ratio,the hardness and fracture toughness of the alloy decrease,while the bending strength increases slightly at first and then decreases.When w(Co)/w(Ni)=5∶5,the hardness,bending strength and fracture toughness of the alloy decrease sharply.With the decrease of w(Co)/w(Ni)ratio,the corrosion potential of the alloy increases,the corrosion current density decreases,and the corrosion resistance of the alloy increases.When the w(Co)/w(Ni)ratio is 7∶3,that is to say,WC-9.8%Co-4.2%Ni alloy has the best comprehensive properties.The synergistic effect of its mechanical properties and corrosion resistance will benefit the service life of the alloy.

关 键 词：w(Co)/w(Ni)比例 硬质合金 力学性能 腐蚀 极化曲线 

分 类 号：TG135.5[一般工业技术—材料科学与工程]