焊后热处理对T92钢焊接接头组织及性能的影响

通过模拟现场热处理工艺，研究了T92钢焊接接头在不同回火温度下的组织和性能。结果表明，焊缝硬度和母材抗拉强度均随回火温度的升高而降低。接头处未回火的马氏体粗大，呈细针状；740-780℃回火，马氏体组织变细，板条特征明显；超过780℃，马氏体板条特征消失，表现为屈氏体组织；随回火温度升高，母材碳化物产生偏聚，铁素体含量增加；780℃以下回火母材力学性能满足ASME标准要求。

EFFECT OF POST WELDING HEAT TREATMENT ON THE MICROSTRUCTURE AND MECHANICAL PROPERTY OF T92 STEEL WELDING JOINT

The microstructure and mechanical property of T92 steel post welding has been studied through stimulating work condition. The conclusion shows that the hardness of weld joint and tensile strength of base metal fall down with the rise of the temper temperature, quenching martensite has coarse needlelike character. When tempered between 740-780℃, the martensite structure became fine and has apparent lath character, tempered above 780℃, the martensite lath character disappear and the weld joint show troostitic structures. The carbide in the tempered martensite of base metal will aggregate and ferrite content percentage increases with temper temperature arise. It can satisfy the requirements of ASME when temper under 780℃.