我厂过去铸造铁路上用的马铁垫板时,用湿砂型浇铸,铸件在砂型中冷却时间一般都在5分钟以上,因此金相组织中时常发现片状石墨和严重的缩松现象,经过焖火以后,韧性很不好。经过研究,起先利用外冷铁,结果良好。后来更进一步利用铸铁平台的铸造法。铸铁平台是一个定形的小平台,尺寸为 480× 360公厘,高 80公厘,在一边有一个凹口,在凹口部分砌一块普通的耐火砖,防止由直浇口下来的铁水冲坏平 In the past, when casting cast iron railings, the cast iron was cast in wet sand. The cooling time of the castings in the sand mold was usually over 5 minutes. Therefore, flaky graphite and severe shrinkage were often found in the microstructure. After stewing After the fire, toughness is not good. After research, the first use of external cooling iron, the result is good. Later, further use of cast iron platform casting method. Cast iron platform is a small shaped platform, size of 480 × 360 mm, height 80 mm, with a notch on the side, in the notch part of the puzzle to build a common firebrick, to prevent molten iron down from the sprue level