摘要
轴承表面粗糙度是影响轴承寿命、可靠性等的重要因素之一,但目前有关轴承表面粗糙度与其耐蚀性的关系研究较少。为此,采用浸泡试验、开路电位-时间(OCP-t)法、电化学阻抗谱(EIS)等方法,研究了表面粗糙度Ra分别为1.35,1.05,0.15μm的GCr15轴承钢在0.05 mol/L NaCl溶液中的腐蚀行为。结果表明:不同表面粗糙度的试样在0.05 mol/L NaCl溶液中浸泡12 h后,试样表面腐蚀严重程度随Ra的增加而增加;Ra为1.35μm和1.05μm的试样,其腐蚀区域多位于试样表面"缝隙"区域,并沿长条状"缝隙"方向扩展;而Ra为0.15μm的试样,其腐蚀区域则多呈细小点状均匀分布。表面粗糙度越大,其达到相对稳态的时间也越长。不同表面粗糙度试样在高频区均呈容抗弧,低频区出现阻抗收缩现象。在高频区,随表面粗糙度的增加,试样的电化学阻抗模值减小。
The surface roughness is one of important factors that influenced the service life and reliability of bearing steel,but the researches on the relationship between the surface roughness and corrosion resistance of bearing steel has been less reported. Herein,the corrosion behavior of GCr15 bearing steel with different surface roughness Ra( 1.35,1.05,0.15 μm) in 0.05 mol/L Na Cl solution was studied by immersion test,open circuit potential-time( OCP-t) and electrochemical impedance spectroscopy technique( EIS). Results showed that the degree of corrosion of the GCr15 samples with different surface roughness became more severe for the samples with bigger Raafter immersed in 0.05 mol/L for 12 h. For the samples with the Ravalues of 1.35 μm and 1.05 μm,the corrosion zones occurred in the scratched gaps regularly,and extended along the gaps. However,for the samples with the Ravalue of 0.15 μm,the corrosion zones equally distributed on the surface of samples and seemed like small dots. For the samples with bigger Ra,the open circuit potentials needed more time to reach a relative stable state.Additionally,the samples with different Ravalues presented the phenomena of the capacitance reactance at high frequencies and the decreasing impedance at low frequencies. With the increase of Ra,the absolute value of electrochemical impedance was reduced at high frequencies.
作者
吴祥锋
方可伟
李成涛
罗坤杰
武焕春
张度宝
WU Xiang-feng;FANG Ke-wei;LI Cheng-tao;LUO Kun-jie;WU Huan-chun;ZHANG Du-bao(Plant Life Management Research Center,Suzhou Nuclear Power Research Institute,Suzhou 215004,China)
出处
《材料保护》
CAS
CSCD
2021年第1期85-89,共5页
Materials Protection
