无金属粘结相硬质合金的电化学腐蚀行为  

Electrochemical corrosion behaviors of binderless carbides

作　　者：马鋆[1] 张立[1] 单成[1] 雷霆[1] 程鑫[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《粉末冶金材料科学与工程》2011年第6期820-826,共7页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金资助项目(51074189;50823006);湖南省科技计划重点项目资助项目(2010FJ2006);高等学校博士学科点专项科研基金资助项目(20100162110001);国家科技重大专项资助项目(2009ZX04012-032;2011BAE09B02)

摘　　要：采用1 700℃、20 MPa高温高压固相烧结工艺制备WC-0.5Cr3C2-0.3VC、WC-3.65TiC-2.45TaC-0.47Cr3C2-0.28VC和WC-6Mo2C-0.47Cr3C2-0.28VC等3种无金属粘结相硬质合金。采用CHI 660C电化学工作站研究在pH=1的H2SO4溶液、pH=7的Na2SO4溶液和pH=13的NaOH溶液中3种合金的电化学腐蚀行为。结果表明,在pH=1的H2SO4溶液和pH=7的Na2SO4溶液中WC-6Mo2C-0.47Cr3C2-0.28VC合金的耐腐蚀性能最好,在pH=13的NaOH溶液中WC-3.65TiC-2.45TaC-0.47Cr3C2-0.28VC的耐腐蚀性能最好。3种无金属粘结相硬质合金在pH=13的NaOH溶液中的耐腐蚀性能均优于其在pH=1的H2SO4溶液中的耐腐蚀性能。综合比较合金的硬度、耐腐蚀性能以及原材料价格,3种合金中WC-6Mo2C-0.47Cr3C2-0.28VC合金具有更佳的性价比。The WC-0.5Cr3C2-0.3VC, WC-3.65TiC-2.45TaC-0.47Cr3Cz-0.28VC and WC-6Mo2C-0.47Cr3C2-0.28VC binderless carbides were prepared by solid phase sintering at the temperature of 1 700℃ and pressure of 20 MPa. Electrochemical corrosion behaviors were investigated in H2SO4 solution （pH=l）, Na2SO4 solution （pH=7） and NaOH solution （pH=13）. The results show that, WC-6Mo2C-0.47Cr3C2-0.28VC alloy exhibits the best corrosion resistance in H2SO4 solution （pH=1） and Na2SO4 solution （pH=7）; while, WC-3.65TiC-2.45TaC-0.47Cr3C2-0.28VC alloy exhibits the best corrosion resistance in NaOH solution （pH=13）. All the three alloys exhibit better corrosion resistance in NaOH solution （pH=13） than that in H2SO4 solution （pH=l）. Considering the hardness, corrosion resistance and the cost of the raw materials of the alloys, WC-6Mo2C-0.47Cr3C2-0.28VC alloy is characterized with a higher performance price ratio among all the three alloys.

关 键 词：无金属粘结相 硬质合金 电化学腐蚀 Tafel曲线 Nyquist图谱 

分 类 号：TG135.5[一般工业技术—材料科学与工程] TG174.36[金属学及工艺—合金]