固溶温度对S32760双相不锈钢组织和拉伸性能的影响  

Effects of Solid Solution Temperature on Microstructure and Tensile Properties of S32760 Duplex Stainless Steel

作　　者：马丽[1] 要玉宏[2] MA Li;YAO Yuhong(School of Aeronautical Materials Engineering,Xi'an Aeronautical Polytechnic Institute,Xi'an 710089,China;School of Materials Science and Chemical Engineering,Xi'an Technological University,Xi'an 710021,China)

机构地区：[1]西安航空职业技术学院航空材料工程学院,陕西西安710089 [2]西安工业大学材料与化工学院,陕西西安710021

出　　处：《热加工工艺》2021年第16期112-116,共5页Hot Working Technology

基　　金：国家自然科学基金资助项目(51371132);西航职院自然科学项目(19XHZK-009)。

摘　　要：为研究固溶温度对轧制态S32760双相不锈钢组织和性能的影响,采用金相显微分析、原位拉伸试验和扫描电镜分析等手段对经不同温度固溶处理的S32760钢的金相组织、拉伸力学性能以及拉伸断裂机理进行了研究。结果表明:轧制态S32760钢的金相组织由铁素体和奥氏体两相组成。经850℃固溶处理后,在铁素体和奥氏体相界析出了大量块状或长条棒状的σ相。随着固溶温度升高,σ相尺寸先减小(950℃)而后σ相完全固溶于基体中(1050℃和1100℃)。经850℃固溶处理后,S32760不锈钢的拉伸强度最高而塑性最差,而经1050℃固溶处理后具有最佳的综合力学性能。850℃固溶态试样拉伸断裂方式为脆性断裂,而轧制态和950℃以上固溶态试样的拉伸断裂方式主要为韧性断裂。In order to clarify the influence of the solid solution temperatures on the microstructure and properties of as-rolled S32760 duplex stainless steel, the microstructure, in-situ tensile properties and tensile fracture mechanism of S32760 steel treated at different solid solution temperatures were investigated by means of metallographic microanalysis, in situ tensile test and SEM analysis. The results show that the microstructures of as-rolled S32760 steel consist of ferrite and austenite. After solution treatment at 850 ℃, bulks or long rods of σ phase are precipitated in the ferrite matrix of S32760 steel, and the size ofσ phase decreases treated at the solution temperature of 950 ℃. When the solid solution temperature is over 1050 ℃, σ phase is completely dissolved in the matrix. S32760 steel treated at 850 ℃ has the highest tensile strength and the worst plasticity and it has the best comprehensive mechanical properties treated at 1050 ℃. The tensile fracture mechanism of S32760 steel solution treated at 850 ℃ is brittle fracture, but the tensile fracture mode of the rolled and solid samples above 950℃ is mainly ductile fracture.

关 键 词：S32760双相不锈钢 显微组织 Σ相 固溶处理 拉伸性能 

分 类 号：TG161[金属学及工艺—热处理]