双相不锈钢组织及腐蚀性能研究

The Study on Microstructure and Corrosion Resistance Properties of Duplex Stainless Steel

摘要: 双相不锈钢材料采用固溶处理和控制冷却两种工艺，开展了不同处理工艺下的微观组织、力学性能、耐腐蚀性能研究。双相不锈钢控制冷却工艺处理后抗拉强度、屈服强度、延伸率明显得到提高；断面收缩率、冲击功基本相差不大；两相比例的平衡控制与第二相沉淀析出是提高强度的主要原因；控制冷却状态下强度虽已达到热轧态的强度，远高于固溶态，平均耐蚀性能比固溶态降低14.6%，铁素体增加了晶界和相界的面积，由于氮能够扩大奥氏体相区，有效地控制了相比例的平衡，因而对于沉淀析出造成的耐蚀性能的损失并不大。

Abstract: The article studied the mechanical properties and corrosion resistance of duplex stainless steel materials which processed by control cooling and solution heat treatment. The tensile strength, yield strength and elongation are improved obviously after control cooling treatment. The area reduction rate is not significantly different by two kinds of processing. The balance control of dual phase scale and precipitation of second phase steel can improve the strength of duplex stainless. The mechanical properties of duplex stainless steel which processed by control cooling are reached; it processed by heat-rolling better than solution heat treatment. The corrosion resistant property of duplex stainless steel by control cooling is lower 14.6% than it by solution heat treatment. The ferrite increased Crysta and the grain boundary areas, as the nitrogen can extend austenite phase region and control the balance of dual phase scale. Therefore, corrosion resistant property is guar-anteed.