论文部分内容阅读
采用钨极氩弧焊(TIG)对铁素体钢501B和奥氏体钢316LN进行了焊接,对焊接接头的微观组织和力学性能进行了检测分析。结果表明:铁素体侧热影响区出现了粗大的组织,而奥氏体侧热影响区的晶粒只发生了轻微长大。熔合区形成了晶粒细小的等轴晶,焊核区的中心部分形成了垂直于焊接方向的柱状晶。合金元素在两侧熔合区均发生了一定程度的扩散。焊接接头硬度分布不均,波动较大,且存在硬度陡降的薄弱区。室温拉伸结果显示,试样断裂在316LN母材处,断口为韧性断裂。高温拉伸试样断裂在焊缝区,断裂形式为脆性断裂和韧性断裂相结合的混合断裂。
The ferritic steel 501B and the austenitic steel 316LN were welded by TIG. The microstructure and mechanical properties of the welded joints were analyzed. The results show that the coarse structure appears in the heat affected zone on the ferrite side, while the grain size in the heat affected zone on the austenite side only slightly increases. The fused zone forms a fine grain of equiaxed grains, and the central part of the nugget area forms columnar crystals perpendicular to the welding direction. Alloying elements in both sides of the fusion zone have taken place to some extent the proliferation. Hardness distribution of welded joints is uneven, fluctuating, and there is a sharp decline in the hardness of the weak area. Tensile tests at room temperature showed that the specimen fractured at 316LN base metal and the fracture was ductile. High-temperature tensile specimen fracture In the weld zone, the fracture form is a combination fracture of brittle fracture and ductile fracture.