Super304H奥氏体耐热钢摩擦焊焊接接头持久强度研究

Study on the Endurance Strength of Friction Welding Joint of Super304H Austenitic Heat Resistant Steel

利用"等温线法"对Super304H奥氏体耐热钢摩擦焊焊接接头625℃持久强度试验数据进行外推,表明焊接接头在超超临界机组工作环境下服役是安全可靠的。结果表明,高应力条件,试样断口主要为韧窝断裂,以穿晶断裂为主;低应力条件,试样断口主要为解离断裂,以蠕变断裂为主;蠕变断裂是以孔洞和微裂纹的形核与长大为基础。析出相沉淀强化是Super304H奥氏体耐热钢焊接接头的主要强化手段。

Use "isothermal method" on Super304 H austenitic heat resistant steel friction welding joint 625 ℃ extrapolation of the endurance strength test data and show that welding joints in the ultra supercritical unit working environment was safe and reliable service. The results show that the fracture of the sample is mainly dimple fracture and transgranular fracture under high stress. Under low stress condition, the specimen fracture is mainly dissociation fracture, mainly creep fracture.Creep fracture is based on nucleation and growth of pores and microcracks. Precipitation strengthening is the main strengthening method of Super304 H austenite heat resistant steel welded joints.