以S31803冷轧双相不锈钢管为研究对象,采用扫描电镜观察、α相面积分析、硬度和拉伸测试等手段研究了不同固溶处理温度对其显微组织和力学性能的影响。结果表明,热处理前,双相钢的α/γ两相组织在冷轧变形过程中沿平行轧向明显被拉长,且奥氏体均匀分布在铁素体基体上,由于加工硬化使其硬度增大远超过产品标准范围(≤290 HBW);经不同温度固溶处理后,显微组织中均未发现析出物,且组织均匀细小,硬度下降到产品标准范围内,塑性提高,铁素体相比例和抗拉强度、屈服强度等力学性能均符合要求;但在较高温度固溶处理后,由于发生再结晶晶粒长大,强度和硬度下降,且铁素体相比例(56.77%)偏高。综合考虑,确定固溶处理温度为1050℃。 The cold rolled duplex stainless steel tube S31803 was taken as the research object. The effects of different solution treatment temperatures on the microstructure and mechanical properties were studied by scanning electron microscopy, α-phase area analysis, hardness and tensile test. The results show that the α / γ phase structure of dual phase steel is obviously elongated along the parallel rolling direction before the heat treatment, and the austenite is uniformly distributed on the ferrite matrix. Due to work hardening, the hardness (≤290 HBW). After the solution treatment at different temperatures, no precipitates were found in the microstructure, and the microstructure was even and fine. The hardness decreased to the standard range of the product, and the plasticity increased. The ferrite Phase ratio and tensile strength, yield strength and other mechanical properties are in line with the requirements; but after high temperature solution treatment, due to recrystallization grain growth, strength and hardness decreased, and the ferrite phase ratio (56.77%), High. Taken together, to determine the solution treatment temperature of 1050 ℃.