等离子体源渗氮AISI 304不锈钢在3.5%NaCl溶液中钝化膜的稳定性  

Stability of Passive Film of AISI 304 Austenite Stainless Steel Modified by Plasma Source Nitriding in 3.5% NaCl Solution

作　　者：曹雪梅[1] 赵贝贝[2] 朱雪梅[2] 李广宇[1] 雷明凯[1] CAO Xuemei;ZHAO Beibei;ZHU Xuemei;LI Guangyu;LEI Mingkai(Surface Engineering Laboratory,School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,China;School of Materials Science and Engineering,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]大连理工大学材料学院表面工程研究室,辽宁大连116024 [2]大连交通大学材料科学与工程学院,辽宁大连116028

出　　处：《大连交通大学学报》2018年第4期72-76,共5页Journal of Dalian Jiaotong University

摘　　要：采用等离子体源渗氮技术对AISI 304奥氏体不锈钢进行表面渗氮处理.利用X射线衍射(XRD)、扫描电子显微镜(SEM)和电子探针显微分析(EPMA)技术,并结合电化学交流阻抗(EIS)测试技术和Zsimp Win软件拟合技术研究改性前后AISI 304奥氏体不锈钢的表面组成结构及在3.5%NaCl溶液中钝化膜的稳定性.研究结果表明,等离子体源渗氮AISI 304奥氏体不锈钢表面形成了氮浓度峰值为23.0%、厚度约为17μm的相改性层.改性前后AISI 304不锈钢在3.5%NaCl溶液中浸泡不同时间形成的钝化膜电极过程的等效电路为R(QR);浸泡时间为10 h时,与AISI 304不锈钢相比,γN改性层的钝化膜电阻R_p从3.615×10~4Ω·cm^2增加至3.765×105Ω·cm^2,增大了1个数量级,具有更好的耐点蚀性能.随着浸泡时间增加至48 h,γN相改性层的钝化膜电阻始终高于AISI 304不锈钢1个数量级,保持在105Ω量级,具有良好的稳定性.Plasma source nitriding technology was used to modify AISI 304 austenite stainless steel. The phase structure,surface morphology and nitrogen concentration-depth of the nitrided layer were characterized by X-ray diffractometer,scanning electron microscopy（ SEM） and electron probe microanalyzer（ EPMA）. The pitting corrosion resistance and the stability of the passive film of the nitrided layer in 3. 5% Na Cl solution were investigated by the measurement of electrochemical impedance spectroscopy（ EIS）. The results indicate that the nitrided layer is consisted of monophase γNphase and has a peak nitrogen concentration of 23 at. % with a thickness of 17 μm. After immersing 10 h in 3. 5% Na Cl solution,the passive film resistance Rpof the γNlayer is increased to 3. 765 × 10~5Ω·cm^2 from 3. 165 × 10~4Ω·cm^2 by using an equivalent electric circuit of R（ QR）,compared with oringinal AISI 304 austenite stainless steel. The passive film of the γNlayer has high pitting corrosion resistant. With the immersation time is increased to 48 h,the passive film resistance Rpof theγNlayer is stable to a magnitude of 105Ω·cm^2,and the passive film of the γNlayer has good stability.

关 键 词：等离子体源渗氮技术 AISI 304不锈钢 γNN相 钝化膜 

分 类 号：TG174.445[金属学及工艺—金属表面处理]