溶解扩散焊技术适用于焊补修复各类铸铁件的表面缺陷，特别是加工后发现的缺陷。铸铁件表面缺陷的修复一般采用电弧冷焊、热焊、气焊和补等方法。由于铸铁的可焊性差，采用常规的熔焊方法易产生白日、裂纹等缺陷；电焊、气焊易在熔合区及热影响区产生硬脆相造成加工困难；热? Dissolved diffusion welding technology for welding repair all types of cast iron surface defects, especially found defects after processing. Cast iron surface repair defects commonly used arc cold welding, hot welding, gas welding and  complement and other methods. Due to the poor weldability of cast iron, the conventional welding method is easy to produce defects such as daytime and cracks; welding and gas welding are easy to cause hard and brittle phase in the fusion zone and heat-affected zone to cause processing difficulties;