钛的碳氮化物固溶与单组元对Ti(C,N)基金属陶瓷电化学腐蚀性能的影响  

Effects of Carbonitride Solid Solution and Interstitial Phase on Electrochemical Corrosion Resistance of Ti(C,N)-based Cermets

作　　者：南晴[1] 张立[1,2] 冯于平[1] 万庆磊 柯荣现 王喆[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]硬质合金国家重点实验室,湖南株洲412000

出　　处：《硬质合金》2013年第3期147-153,共7页Cemented Carbides

基　　金：国家自然科学基金资助项目(51074189);高等学校博士学科点专项科研基金资助项目(20100162110001);湖南有色集团-中南大学有色研究基金资助项目(Y2012-010)

摘　　要：以TiC0.7N0.3-10%WC-4%Mo2C-3%TaC-2.4%Cr3C2-10%Ni-10%Co和TiC-10%TiN-10%WC-4%Mo2C-3%TaC-2.4%Cr3C2-10%Ni-10%Co 2种Ti(C,N)基金属陶瓷为研究对象,采用Tafel曲线与Nyquist图谱研究2种金属陶瓷在pH=1的H2SO4溶液与pH=13的NaOH溶液中的电化学腐蚀行为,采用扫描电镜观察合金的腐蚀表面。结果表明,与单组元原料相比,以固溶体为原料制备Ti(C,N)基金属陶瓷在强酸、强碱性溶液中的腐蚀速率均明显降低,耐腐蚀性显著提高;Ti(C,N)基金属陶瓷在碱性溶液中的耐腐蚀性能优于其在酸性溶液中的耐腐蚀性能。Ti(C,N)基金属陶瓷的腐蚀机理是:与腐蚀溶液接触时,合金中粘结相优先发生腐蚀,产生活性溶解,硬质相骨架裸露在合金表面,硬质相发生局部腐蚀。The electrochemical corrosion behaviors of TiC0.7N0.3-10%WC-4%Mo2C-3%TaC-2.4%Cr3C2-10%Ni-10%Co and TiC-10%TiN-10%WC-4%Mo2C-3%TaC-2.4%Cr3C2-10%Ni-10%Co cermets in H2SO4 solution （pH=1） and NaOH solution （pH=13） were investigated by means of Tafel curves and Nyquist plots. The corrosion surface of the eermets was observed by scanning electron microscopy. It is shown that, comparing with the eermets prepared from interstitial phase type of TiC and TiN, the corrosion resistance of the cermet prepared from TiC0.7N0.3 is observably improved in all the electrolytes. The Ti （C,N）-based cermet exhibits better corrosion resistance in the alkaline solution than that in the acid solution. The corrosion mechanism is as following：while the cermet is in contact with the corrosion solution, preferential corrosion and active dissolution take place in the binder phase, and the corrosion reaction takes place on the local region of the hard phase.

关 键 词：TI(C N)基金属陶瓷 电化学腐蚀 Tafel曲线 Nyquist图 

分 类 号：TG148[一般工业技术—材料科学与工程]