焊缝金属对SUPER 304H奥氏体耐热钢焊接性的影响

综述了焊缝金属对SUPER 304H钢焊接性的影响。结果表明,SUPER 304H钢不同成分GTAW奥氏体焊缝的热裂纹倾向较大;焊缝中凝固裂纹倾向主要是受A凝固模式控制,而HAZ液化裂纹倾向的主要原因则与晶界析出相,以及铜的富集等因素有关。不同成分奥氏体焊缝接头的力学性能各异;合适的焊缝化学成分和优化的焊接工艺是获得满意接头综合力学性能的重要技术手段。不同成分形成的"同质"或"异质"焊缝,其微观组织皆为奥氏体+析出相。熔化焊焊缝为A凝固模式,非熔化焊的摩擦焊焊缝为AF凝固(相转变)模式。

Effect of weld metals on weldability of SUPER 304H austenitic heat resistant steel

The influences of weld metals on the weldability of SUPER 304 H steel were reviewed.The results show that the hot crack tendency of GTAW austenitic weld with different composition of super 304 H steel is relatively large;the solidification crack tendency in the weld is mainly controlled by a solidification mode,while the main reason of HAZ liquefaction crack tendency is related to the precipitation phase at the grain boundary and copper enrichment and other factors.The mechanical properties of austenitic weld joints with different compositions are different.Proper weld chemical composition and optimized welding process are an important technical means to obtain satisfactory comprehensive mechanical properties of joints.The microstructures of"similar"or"dissimilar"welds formed by different compositions are all austenite+precipitates.Fusion welds are solidified in A mode,while friction welds that are not fusion welded are solidified or phase-transformed in AF mode.