高频淬火1Cr12Ni2W1Mo1V钢点蚀萌生机理探讨  

INVESTIGATION OF PITTING INITIATION MECHANISM OF 1Cr12Ni2W1Mo1V STEEL AFTER INDUCTION HARDENING

作　　者：董俊[1] 张全慧[1] 周敬恩[2] 王虹[3] 林锦棠[3] 石连峰 

机构地区：[1]中国科学院上海光学精密机械研究所,上海201800 [2]西安交通大学材料科学与工程学院,西安710049 [3]东方汽轮机厂,四川德阳618000

出　　处：《机械强度》2001年第1期32-34,65,共4页Journal of Mechanical Strength

摘　　要：测定了高频淬火后经不同温度回火的 1Cr12Ni2W 1Mo1V钢试样在不同腐蚀环境以及有外加应力作用下的点蚀电位。结果表明 ,1Cr12Ni2W 1Mo1V钢的点蚀萌生不仅与材料的热处理工艺、微观组织以及腐蚀环境有关 ,而且与外加应力有很大的关系。点蚀电位Eb 随氯离子浓度CCl- 增大而降低 ,且Eb 与logCCl- 呈直线关系。对于高频淬火 +低温回火试样 ,在一定氯离子浓度 (4 .373mol/LCl-)下 ,pH值对点蚀电位影响不大 ;而对调质试样 ,pH值对Eb 影响较大。高频淬火后试样的点蚀电位随外加应力变化可分为三个区 :在应力小于 5 0MPa时 ,点蚀电位随应力增加而急剧下降 ;在5 0～ 40 0MPa范围 ,点蚀电位随应力增加而缓慢减小 ;当应力大于 40 0MPa时 ,点蚀电位基本趋于稳定。在此基础上提出了 1Cr12Ni2WPitting potential of the 1Cr12Ni2W1Mo1V steel specimens, which is hardened and tempered at different temperatures, was measured under different corrosion environments and under different stress levels. Test results show that the external stresses have great influence on the pitting initiation of the 1Cr12Ni2W1Mo1V steel besides the material processing, microstructure and corrosion environments. Pitting potentials increase with decreasing of the concentration of chlorine ion and have a linear relationship with log C Cl - . Under a certain concentration of chlorine ion, the effects of pH on the induction hardening specimens after low temperature tempering are negligible, while the effect of pH on the high temperature tempered specimen is relatively great. Pitting potentials decrease dramatically with the increasing of the stress when the stress is lower than 50 MPa; pitting potentials decrease little with the increasing of the stress in the region of 50～400 MPa; pitting potentials tend to be stable when the stress is higher than 400 MPa. Based on the test results, a mechanism of passive film cracking was also presented.

关 键 词：应力 点蚀 钝化膜 汽轮机 叶片 1Cr12Ni2W1Mo1V 钢 

分 类 号：TK263.3[动力工程及工程热物理—动力机械及工程] TG172.9[金属学及工艺—金属表面处理]