工具钢在磷酸盐缓冲液中的电化学性能  

Electrochemical Properties of Tool Steels in Phosphate Buffer Saline Solution

作　　者：张志英 岳姝敏 龚焱龙 杨潇 陈涛 张覃轶[1,2] Zhang Zhiying;Yue Shumin;Gong Yanlong;Yang Xiao;Chen Tao;Zhang Qinyi(School of Materials Science and Engineering,Wuhan University of Technology;Yangjiang Alloy Laboratory;Xiangyang City Liqiang Machinery Co.,Ltd.)

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070 [2]阳江合金材料实验室 [3]襄阳市立强机械有限公司

出　　处：《特种铸造及有色合金》2023年第9期1162-1167,共6页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51502229);武汉理工大学博士科研启动基金资助项目(471-40120189)。

摘　　要：通过动电位极化法、电化学阻抗图谱法、光学显微镜、扫描电镜、能谱分析和X射线光电子能谱研究了4V、S35VN、14C28N、BD1N工具钢在磷酸盐缓冲液(Phosphate Buffer Saline,PBS)中的腐蚀和电化学性能,并与奥氏体不锈钢304和316L进行对比。动电位极化结果表明,试样在PBS溶液中均发生了钝化,显示良好的耐腐蚀性。电化学阻抗图谱结果表明,电极过程由电化学反应步骤控制。4V钢的自腐蚀电位Ecorr最低,为-0.766 V_(SCE),腐蚀电流密度J_(corr)最大,为6.61×10^(-5)A/cm^(2),容抗弧半径最小,钝化膜电阻和电荷转移电阻之和Rf+Rct值最小,为1.00×10^(3)Ω·cm^(2),耐腐蚀性最差。耐腐蚀性为4V<S35VN<14C28N<BD1N<304<316 L。在PBS溶液中,工具钢试样均发生点蚀。4V钢的Cr含量较低,耐蚀性较差。BD1N、14C28N和S35VN的Cr含量较高,钝化膜较稳定,耐蚀性良好。奥氏体不锈钢316L和304的Cr和Ni含量较高,生成稳定的钝化膜,耐蚀性优良。The corrosion and electrochemical properties of several tool steels,including 4V,S35VN,14C28N and BD1N,in phosphate buffer saline(PBS)solution were investigated by potentiodynamic polarization tests,electrochemical impedance spectroscopy(EIS),optical microscopy,scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDS)and X-ray photoelectron spectroscopy(XPS),and compared with austenitic stainless steels 304 and 316L.The potentiodynamic polarization results illustrate that passivation occurs in all specimens,indicating desirable corrosion resistance in PBS solution.EIS results reveal that the electrode process is controlled by electrochemical reaction steps.Spontaneous corrosion potential E corr of 4V steel is the lowest,which is-0.766 V_(SCE),while corrosion current density J_(corr)is the highest,which is 6.61×10^(-5)A/cm^(2),and capacitance arc as well as the sum value of passivation film resistance R and charge transfer resistance Ret are the smallest,where the latter is 1.00×10^(3)Ω·cm^(2),leading to the worst corrosion resistance.The sequence of corrosion resistance is presented as follows:4V<S35VN<14C28N<BD1N<304<316 L.Localized corrosion occurs in all the tool steels in PBS solution.Cr content in 4V steel is lower,resulting in the poor corrosion resistance,while that in S35VN,14C28N and BD1N are high,contributing to the stable passivation films and desirable corrosion resistance.The high Cr and Ni content in 304 and 316L austenitic stainless steels is helpful to the stable passivation films,giving rise to excellent corrosion resistance.

关 键 词：工具钢 磷酸盐缓冲液 电化学性能 腐蚀 

分 类 号：TG142.4[一般工业技术—材料科学与工程] TG172.9[金属学及工艺—金属材料]