胎体组分对热压孕镶金刚石钻头胎体腐蚀磨损性能的影响  

Effect of composition on abrasion-corrosion behavior of WC-based matrix material for impregnated diamond bits

作　　者：刘志江 姚远基 王文正 潘秉锁[1] LIU Zhijiang;YAO Yuanji;WANG Wenzheng;PAN Bingsuo(Faculty of Engineering, China University of Geosciences (Wuhan), Wuhan 430074, China)

机构地区：[1]中国地质大学(武汉)工程学院,武汉430074

出　　处：《金刚石与磨料磨具工程》2021年第2期75-81,共7页Diamond & Abrasives Engineering

基　　金：国家自然科学基金面上项目(41872187)。

摘　　要：为研究WC、Fe、663Cu等3种胎体组分质量分数对热压孕镶金刚石钻头胎体腐蚀磨损性能的影响,在pH为10,NaCl质量分数为20%的盐水环境下进行腐蚀磨损试验、静态腐蚀试验和电化学测试,并观察分析试样表面形貌和腐蚀产物。结果表明:在盐水环境下,机械磨损在腐蚀磨损中占据主导地位,纯腐蚀影响不明显,但二者之间的协同作用引起的胎体质量损失不容忽视。随着胎体耐腐蚀性的减弱,协同作用更加显著。静态腐蚀结果表明:WC和Fe质量分数的增加会使得胎体耐蚀性减弱,而663Cu恰恰相反。腐蚀产物主要是铜铁氧化物和羟基氯化物。腐蚀磨损过程中,由于不同胎体组分之间存在电位差,在盐水介质中形成以Fe等黏结相作阳极,以WC作阴极的微电偶,使得黏结剂材料被优先去除,WC颗粒失去支撑后更易在机械作用下被去除。整个磨损过程新鲜表面的暴露和钝化会达到平衡,在腐蚀磨损停止后试样表面会迅速发生钝化。To study the influence of the component(WC,Fe and 663Cu)contents on the abrasion-corrosion properties of impregnated diamond bit matrix,abrasion-corrosion tests,static corrosion tests and electrochemical tests were carried out in 20%NaCl slurry with pH value of 10.The surface morphology and corrosion products were observed and analyzed by SEM and Raman spectroscopy.The results show that mechanical wear plays a dominant role in abrasion-corrosion process in salt water environment,and pure corrosion has no obvious effect.However,the synergistic effect of these two components cannot be ignored.With the decrease in corrosion resistance of the matrix,the synergistic effect was more significant.Furthermore,the anti-corrosion property of the matrix deteriorated with the increase of WC and Fe contents,but the opposite was true for 663Cu.The dominant corrosive products have been detected as a mixture of oxides and hydroxy chloride.Due to the potential difference between different matrix components,Fe and other binder phases were formed as anode and WC as cathode in the process of abrasion-corrosion.The micro galvanic couple between WC and binder removed binder material preferentially.And WC particles were removed more easily under mechanical action after losing support from the binder.During the process of test,the exposure and passivation of the fresh surface will reach a balance.After the abrasion-corrosion test,the sample surface will be passivated rapidly.

关 键 词：孕镶金刚石钻头 腐蚀磨损 胎体组分 盐水泥浆 

分 类 号：TG74[金属学及工艺—刀具与模具]