基于泡沫模原型的消失模复合型壳制备工艺

Preparation Process of Compound Shell for Lost Foam Casting Based on Foam Pattern Prototypes

利用发泡成型工艺制备高质量的泡沫模原型,在泡沫模表面制作2～3层硅溶胶-水玻璃复合陶瓷型壳,之后采用自硬水玻璃砂作陶瓷型壳背衬。陶瓷型壳在200～250℃保温30min失模及二氯甲烷溶剂溶失方式失模,焙烧工艺为800℃保温1h。结果表明,该制壳工艺简单、周期短、成本低,制得复合型壳表面光洁、强度高,并浇注出了质量较高的ZL101合金铸件。

A new process of compound mold shell for lost foam casting was presented based on foam pattern, which utilized foaming confection to get high quality foam pattern prototypes, then prepared 2~3 layers compound ceramic shell of silica sol-sodium silicate on the surface of foam pattern, finally, prepared the backup layer of ceramic shell with no-bake sand. Dewaxing of ceramic mold shell was carried out in methylene chloride dissolvent at 200~300℃ for 30 min, and then the ceramic mold shell was baked at 800 ℃ for 1 h. The results reveal that the shell-making process has the features of simply and short period as well as low cost. The prepared compound shell possesses clean surface and high strength. Meanwhile, ZL101 alloy castings with high quality were obtained with the compound shell.