大型复杂不锈钢叶轮熔模-砂型复合铸造工艺

研究了大型复杂不锈钢叶轮熔模-砂型复合铸造工艺。借助设计的工装,利用熔模铸造涂制出复杂叶片部分的硅酸乙酯-水玻璃复合型壳;利用砂型造型得到简单轮毂轮辐及熔模型壳部分的铸型;将熔模型壳与水玻璃砂型组合后得到了该叶轮的熔模-砂型复合铸型;通过熔炼、浇注、切割、清理、热处理得到了ZG1Cr18Ni9Ti叶轮铸件。结果表明：采用该复合工艺生产的叶轮铸件表面粗糙度达到Ra3.2-1.6、尺寸精度达到CT4-CT5、力学性能等都满足技术要求,且工艺稳定,生产成本低。

Study on the Compound Precision Casting and Sand Casting Technology of a Large Complicated Stainless Steel Impeller

The compound casting technology of a large complicated stainless steel impeller was studied through precision casting and sand casting. Parts of complicated blade were made into the silicone-water glass composite shell by precision casting; simple hubs and spokes, and the precision shell were made by sand casting method, then all of them were combined together to obtain an impeller compound mould with precision casting shell and sand mould. ZG1Cr18Ni9Ti impeller casting is produced by melting, pouring, cutting and heat treatment. The results show that the surface roughness and precision of the casting can reach Ra3.2~, 1.6 and CT4-CT5 respectively. Its mechanical properties can meet the specification requirements. The combined technology is stable and has low cost.