一、用HO8Mn2SiA细丝CO_2冷焊铸铁存在问题采用HO8Mn2SiA细丝CO_2保护冷焊国内已有应用。我们经三年多的研究及通过大量实践,发现主要还存在以下问题: 1.焊缝熔合区的微气孔问题。这主要是由于熔合区的含碳量总是比焊缝中心高,还由于CO_2焊有一定的氧化性。在1500℃以上时,碳已比Mn、Si具有更高 First, with HO8Mn2SiA filament CO_2 cold welding cast iron problems HO8Mn2SiA filament CO_2 cold welding has been the application of domestic. After more than three years of research and through a large number of practices, we found that there are mainly the following problems: 1. Microporosity in weld zone. This is mainly due to the carbon content of the fusion zone is always higher than the center of the weld, but also due to CO 2 welding a certain degree of oxidation. Above 1500 ° C, carbon has a higher density than Mn and Si