热等静压316L不锈钢致密体的组织与性能

采用热等静压方法对气雾化316L奥氏体不锈钢粉末致密化，用箱式电阻炉对致密体进行了固溶处理，研究了固溶前后致密体的显微组织和力学性能，并对其拉伸断口形貌进行了分析．结果表明：热等静压态致密体密度接近理论全致密，内部组织为细小的奥氏体，存在较多的碳化物，抗拉强度、屈服强度分别达到595．3MPa和263．3MPa，延伸率为58．3％，硬度为HBS152．3；固溶处理使致密体强度和硬度降低，塑性增加，且随着固溶温度的提高，强度迅速降低，塑性明显提高，最佳固溶温度为1050℃；在固溶温度为1050℃和水冷的情况下，最佳保温时间为20min；固溶处理前后拉伸试样断口呈现明显的韧性断裂，固溶韧性好于固溶前的，均高于热轧态产品的韧性．

Microstructure and properties of 316 L stainless steel prepared by hot isostatic pressing

Gas atomized pre-alloyed 316 L stainless steel powder was consolidated by hot isostatic pressing(HIP).Solid solution was implemented on the compact using a box resistor furnace.The microstructure and mechanical properties of the dense body was investigated.The results show that the fully dense body has homogeneous microstructure and fine grain size.The microstructure is composed of austenite with plenty of carbide particles.The values of tensile strength,yield strength,elongation and hardness of the dense body are 595.3 MPa,263.3 MPa,58.3% and HBS 152.3,almost as well as that of the hot-rolled products.The strength and hardness of the dense body were reduced by Solution treatment,and its elongation was enhanced.Strength of the steel decreases and its elongation increases with increasing heating temperature,the best solution temperature is 1 050 ℃.The best holding time is 20 min when the solution temperature is 1 050 ℃ and the thickness of specimen is 2 mm.The fracture of specimen presents ductile fracture,no matter in the hot isostatic pressed specimens or the heat treated specimens.