摘要
为了研究双相不锈钢热加工过程中稀土对有害析出相的影响,采用电化学动电位极化扫描法、电化学交流阻抗谱法、扫描电镜、电子探针及X射线衍射等方法研究了镧、铈混合稀土对2205双相不锈钢耐腐蚀性能的影响。结果表明:稀土优先富集在双相不锈钢δ/γ相界及其附近地区,并且使得钢中δ/γ相界处合金元素Cr和Mo的富集程度减小,延缓了σ相的析出;在1.0 mol/L Na Cl+0.5 mol/L HCl溶液中,稀土增大了双相不锈钢的钝化区间,降低了其钝化电流密度,能够阻止腐蚀性阴离子向钝化膜内部扩散;稀土通过延缓σ相的析出,提高了双相不锈钢的耐腐蚀性能。
Effects of La and Ce on harmful precipitation phase and aging treatment on corrosion resistance of 2205 duplex stainless steel（ DSS） during hot working process were investigated by electrochemical tests,electrochemical impedance spectroscopy,scanning electron microscopy,electron probe microscopic analyzer and X-ray diffraction. The results show that the enrichment of Cr and Mo on δ / γboundaries is reduced,and the precipitation of σ phase is effectively inhibited,because RE are preferentially segregated at δ / γboundaries. The corrosion resistance of DSS2205 steel with 0. 035% RE is improved by retarding the precipitation of σ phase. The potentiodynamic polarization tests indicate that the passive range is increased,and the passive current density is decreased and the inward diffusion of the corrosion anion in passive film growth of DSS2205 steel is suppressed by the addition of RE.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2016年第1期112-118,共7页
Transactions of Materials and Heat Treatment
基金
国家"863"计划项目(2010AA03A407)
国家自然科学基金(51474088)
河北省自然科学基金(E2013209307)
河北省教育厅研究项目(QN2014080)
关键词
稀土
双相不锈钢
析出相
耐腐蚀
rare earth
duplex stainless steel
precipitated phase
corrosion resistance
