消失模铸件夹砂和夹渣缺陷的成因及对策

Sand Inclusion and Slag Inclusion Formation Reasons and Countermeasures of Lost foam Castings

由于在消失模铸造生产过程中涂料层的剥落、开裂和裂纹以及浇注系统封闭不严密等原因将导致砂粒、涂料和夹杂物随着液体金属进入铸件,是造成铸件夹砂和夹渣缺陷的主要原因。指出提高涂料的强度、耐火度,精心装箱操作,采用正确的负压浇注工艺参数,集渣挡渣撇渣技术以及铁液过滤、净化技术等,可以减少和消除夹砂、夹渣缺陷。

It is the main reasons of sand inclusion and slag inclusion defects formation of castings that the scaling off and cracking of the coating layer as well as the gating system being not properly sealed during the lost foam casting process which causing the sand particles,coating and other impurity inclusions entering the casting together with the molten.It was pointed out that the sand and slag inclusions defects could be reduced and eliminated by adopting correct vacuum pouring parameters,slag collecting and skimming techniques,as well as the molten iron filtering and purifying techniques.