黄昌虎,宋新莉,贾涓,范丽霞

• 1:武汉科技大学耐火材料与冶金国家重点试验室

摘要(Abstract)：

首先对Cr18Ni10Ti不锈钢进行1050℃固溶处理及650℃时效24 h处理,随后在不同温度(500～800℃)下以1.43×10~(-4) s~(-1)拉伸速率对其进行高温拉伸试验。采用扫描电镜与能谱仪分析了试验钢的组织、析出相及断口形貌,采用高分辨透射电镜观察其位错和晶界处的P和S元素的浓度。结果表明:Cr18Ni10Ti不锈钢的组织主要是奥氏体组织,基体中有富Cr析出相及AlMgTiO复合析出相。当拉伸温度从500℃升高到800℃时,试验钢的屈服强度、抗拉强度均减小,断面收缩率先减小后增大,在650℃拉伸时,断面收缩率最小。当拉伸温度较低时,试验钢出现明显的颈缩现象,随拉伸温度升高,拉伸过程中的颈缩现象不明显,出现韧窝与沿晶混合断口。当拉伸温度升高到800℃时,试验钢发生蠕变断裂,出现冰糖状断口。第二相、拉伸过程的回复与再结晶、P和S元素的晶界偏聚行为以及晶界蠕变等多种因素的影响使得Cr18Ni10Ti不锈钢在500～800℃拉伸时出现不同的强度与断面收缩率。

关键词(KeyWords)： 不锈钢;拉伸温度;断口形貌;位错;晶界偏聚

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51871064)

作者(Author): 黄昌虎,宋新莉,贾涓,范丽霞

DOI: 10.13289/j.issn.1009-6264.2021-0151

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