一种节镍经济型耐热铸钢的点蚀行为研究.pdfVIP

学兔兔 Oct．2O15 VOI．64 NO．1O ·955· 一 种节镍经济型耐热铸钢的点蚀行为研究 吴林才，安立聪，杨弋涛 (上海大学材料科学与工程学院，上海200072) 摘要：在ZG40Cr25Ni20的基础上降低Ni的含量，增加cr、Mo的含量，获得一种经济节镍型耐热铸钢。通过在6％的 FeC1 溶液中浸泡测得材料的失重曲线，并运用循环极化方法研究它们在3．5％Nacl溶液中的点蚀行为，借助SEM扫描 电镜、x射线面扫描及EDX能谱探究了材料表面点蚀萌生及发展的机理，通过增加cr和Mo的含量，cr的添加有利于 形成致密的可通过再钝化过程实现自我修复的含cr的钝化膜，Mo的添加有利于形成覆盖在点蚀坑上的MoO ，可提 高材料的耐点蚀性能。 关键词：耐热钢；点蚀；钝化膜 中图分类号：TG142．73 文献标识码：A 文章编号：1001—4977(2015)10—0955—05 Pitting Corrosion Behavior of a Low Nickel Heat Resistant Cast Steel WU Lin—cai．AN Li—cong．YANG Yi·tao (School ofMaterials Science and Engineering,Shanghai University,Shanghai 200072，China) Abstract：To obtain an economic low nickel heat resistant cast steel on the basis ofZG40Cr25Ni20。reducing the amount ofNi and increasing the amount ofCr,Mo．weight lOSS curves Oftwo kinds ofheat resistant cast stee1 were gained by soaking in 6wt％FeC1 solution．Cyclic polarization measurement in 3．5wt％NaCl was used to study the pitting corrosion behavior of two heat resistant stee1．Additionally,the mechanism of the corrosion attack developed on the material surface was researched by scanning electron microscope(SEM)．chemical microanalysis by energy dispersive spectrometry(EDS)，X-ray mapping analysis．with the amount of Cr，Mo increasing,the Cr can promote the passive film foITn and passive film is compact and selfrepair can be achieved by repassive process，MoO3 can be formed on the surface of pitting corrosion pit by adding Mo，the pitting corrosion resistant property was increased． Key words：heat resistant steel；pitting corrosion；passive fllm 耐热钢具有优良的高温力学性能和热加工性能， 扫描电镜、x射线面扫描及EDx能谱探究了材料表面