基于无模铸造精密成形技术的型砂切削性能研究

Research of Cutting Properties of Mold Sand Based on the Precision Forming Technology Without Pattern

基于无模铸造精密成形技术的复合铸型工艺可为复杂铸件高质量铸造提供解决方案。本文通过对复合铸型工艺用各种型砂（包括硅砂、宝珠砂、铬铁矿砂、锆英砂以及钢丸混砂等）的力学性能及切削性能进行深入研究，得知：型砂的抗拉强度随着树脂和固化剂含量的增加而增大，达到一定值后下降；砂型切削力与型砂抗拉强度呈正比关系，砂型表面尺寸相对误差随着抗拉强度的增加呈现先减小后增大的趋势，抗拉强度值在0．8～15MPa时其切削性能较好。同时，研究获得了复合铸型用型砂最优配比范围。本文研究成果可为复杂金属件高质量铸造提供技术保障。

The compound mold process, based on the digital precision forming technology without pattern casting, provides a solution of complex castings＇ manufacturing with high quality. By researching the cutting properties of compound mold process mold sand, including silica sand, ceramic foundry sand, iron ore sand, zircon sand, steel shot sand, etc, the results have been obtained as follows. The tensile strength of sand mold increases firstly, and then decreases, with the increasing of the resin and the hardener content. The cutting force of sand mold is proportional to its tensile strength. The surface dimensional relative error increases firstly, and then decreases, with the increasing of the tensile strength. When the value of the tensile strength of sand mold is 0.8-1.5 MPa, its cutting property is good. The optimal ratio of mold sand in compound mold has been gotten. The results will provide the technical support of complex castings＇ manufacturing with high quality.