碳钢轮毂铸件的消失模铸造

Lost Foam Pattern Casting of Carbon Steel Wheel Hub

介绍了碳钢轮毂铸件的结构特点及技术要求,利用消失模铸造工艺进行试生产,浇注时发生反喷、塌箱以及铸件增C现象等。对其原因进行了分析:轮毂白模密度过高、不均匀,气化时产生大量的气体,使得铸型内部气压急剧上升而产生反喷;当气化过快,造成真空度不足,涂料强度低,浇注时容易产生塌箱;浇注时泡沫燃烧分解出游离C,C侵入钢液致使铸件增C。采用空心浇注系统、提高浇注温度等办法,经过多次试验,基本上克服了消失模生产铸钢件产生的缺陷。铸件加工后的合格率在90%以上,符合客户产品的技术要求。

The configuration characteristics and technical requirements of carbon steel wheel hub casting were introduced.However,on the trial of using lost foam pattern casting process,reverse spray during pouring,mould collapse and casting recarburation occurred. The reasons of above problems were analyzed：the lost foam pattern density was too high and not uniform,therefore it generated large amount of gas when it was gasifying and such caused inner gas pressure of the mould cavity suddenly rising,and as the result,the reverse spray occurred. Gasifying too fast could cause vacuum deficiency and low coating strength and such caused mould collapse. The foam plastic burned during pouring,decomposed and produced dissociated C which penetrated into steel melt and caused recarburation. Repeating test were conducted by using hollow gating system pattern and increasing pouring temperature has basically eliminated above mentioned defects. Qualifying rate of castings after machining was of higher than 90%,and product quality met client＇s technical requirements.