焊缝金相主要是研究焊接接头的宏观组织和显微组织。由于焊接过程中,热源作用强烈,焊接热循环及焊接冶金具有一系列的特殊性,因此熔池金属的结晶及焊接接头的金相组织对接头的质量有很大的影响。焊缝金相是确定焊接接头质量的基本指标之一,研究焊缝金相可以了介金属的可焊性,确定焊接工艺规范的合理性,以及推断焊接结构长期高温运行的可靠性。电站目前主要采用电弧焊及气焊两种焊接方法。随着我国电力工业的飞跃发展,焊接应用日益广泛。电站常用钢种的焊接工艺规范见表 Weld metallography is mainly the study of welded joints of the macro-organization and microstructure. As the welding process, the heat source is strong, the welding heat cycle and welding metallurgy has a series of special characteristics, so the crystallization of the molten pool metal and welded joint metallurgical structure of the joint have a great impact on the quality. Weld metallography is to determine the quality of welded joints, one of the basic indicators of the weld metal microstructure can be metal-based solderability, to determine the welding process specification is reasonable, and infer the long-term high-temperature welded structure reliability. At present, the power station mainly adopts arc welding and gas welding two kinds of welding methods. With the rapid development of China’s power industry, welding applications are increasingly widespread. Power station commonly used steel welding process specifications table