基于有限元分析的准晶磨料强化不锈钢表面钝化行为  

Passivation Behavior on the Surface of Stainless Steel Reinforced by Quasicrystal-Abrasive via Finite Element Simulation

作　　者：陈永君 白妍 董闯[2,3] 解志文 燕峰 吴迪[1] CHEN Yongjun;BAI Yan;DONG Chuang;XIE Zhiwen;YAN Feng;WU Di(School of Mechanical Engineering and Automation,University of Science and Technology LiaoNing,Anshan 114051,China;Key Laboratory of Materials Modification by Laser,Ion and Electron Beams,Ministry of Education,Dalian University of Technology,Dalian 116024,China;Institute of Optoelectronic Materials and Device,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]辽宁科技大学机械工程与自动化学院,鞍山114051 [2]大连理工大学三束材料改性教育部重点实验室,大连116024 [3]大连交通大学光电材料与器件研究所,大连116082

出　　处：《金属学报》2020年第6期909-918,共10页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目Nos.51901094、51771087;辽宁省博士科研启动基金计划项目No.2019-BS-124;辽宁省创新人才支持计划项目No.LR2017052;辽宁科技大学基金项目Nos.2019RC06、601011507-07。

摘　　要：分别选用金刚石、Al2O3和准晶的单颗粒切削模型对不锈钢表面进行有限元仿真,定性表征准晶磨料对不锈钢表面的作用特点,结合硬度、Mott-Schottky曲线和动电位极化曲线等实验结果,综合分析准晶磨料强化不锈钢表面钝化膜的耐蚀机理。结果表明,经准晶单颗粒磨料反复磨削后,不锈钢表层的等效塑性应变最大,最高可达73%,此结果与实测的碾磨系数变化规律相符。经准晶处理的不锈钢,其纵向影响层表现出较高的梯度等效应力分布特点,与实验测得的不锈钢表层不同深度硬度的变化规律一致,即准晶磨料处理的不锈钢的硬度在不同深度的影响层都保持最高值。Mott-Schottky曲线最低载流子浓度表明,准晶磨料处理的不锈钢表面形成比较完整的钝化膜;动电位极化曲线最小维钝电流密度说明准晶处理的不锈钢表面更容易钝化。The quasicrystal(QC)-abrasive wear produces a flattened surface compared with traditional abrasives when used to polish metals,opening up new application fields for QC in particle form,butthe influence range and extent of QC-abrasive on metal surface are not clear.In this work,the single particle grinding model was used for finite element simulation to qualitatively characterize the effect of QCabrasive on the subsurface of stainless steel,which was ground by diamond,Al2 O3 and QC single particle abrasive,respectively.The effects of three kinds of abrasives on the equivalent stress and strain of stainless steel surface were compared.Combined with the measurement of the gradient hardness of stainless steel subsurface,the Mott-Schottky plots and potentiodynamic polarization curve were given,analyzing the corrosion resistance mechanism of passivation film formed on the surface of stainless steel pretreated with QC-abrasive.The results show that the equivalent plastic strain of the stainless steel surface is the highest,up to 73%,when it is ground by QC single particle abrasive repeatedly for six times,which is consistent with the smearing coefficient measured in the experiment.The smearing-dominating on the surface of stainless steel treated with QC-abrasive is strengthened with time increased,but diamond and Al2 O3 abrasives are improved cutting-dominating with time increased.At the same time,a large number of plastic deformation areas accumulated a higher stress,longitudinal sub-surface of stainless steel treated by QC-abrasive show a higher gradient distribution of equivalent stress.The simulation results are consistent with the changes of hardness of stainless steel at different depths measured in the experiment.The hardness of QC-abrasive treated stainless steel maintains the highest value at 200,400 and 1800 nm to the surface,respectively.It is manifested as the gradient law of gradual decrease from the surface layer to the interior of the matrix.The Mott-Schottky plots with the minimum carrier concentration p

关 键 词：准晶磨料 有限元仿真 不锈钢 塑性变形 耐蚀性 

分 类 号：TG739[金属学及工艺—刀具与模具]