縮孔、气孔、砂眼和裂紋是鑄鉄件常見的缺陷;如果它們产生在不加工面上,一般可以用鑄鉄焊条焊补;产生在加工面上,就要用蒙納尔合金焊条焊补。对于这些缺陷过去我們曾經用鑄鉄焊条来焊补,但由于白口問題沒有解决而沒有获得成功。目前鎳、銅材料供应困难,无法配制蒙納尔合金焊条,我們只好再次試驗用鑄 Craters, pores, blisters and cracks are the common defects of castings; if they are produced on unprocessed surfaces, they can generally be welded with cast-in electrodes; produced on the machined surfaces, . In the past, we used to use cast iron welding rod to make up for these defects, but did not succeed because the white issue was not solved. At present, nickel, copper material supply difficulties, unable to formulate Monel alloy electrode, we had no choice but to test the use of cast