消失模铸造工艺回用旧砂性能的研究

许多厂家反映消失模生产旧砂多次回用后严重影响铸件品质，选取消失模生产线上回用旧砂为样品，对型砂的粒度分布、灰分含量、灼减量、透气性，流动性等基本性能进行了测试，同时对新砂样品进行对比测试；试验结果表明，旧砂中涂料碎片增多，砂粒之间磨损增加，残留热解产物增多，是导致旧砂基本性能变差的根本因素。

Investigation on the Properties of the Used Sand in the Lost Foam Casting Process

Many lost foam casting producers have found that the properties of the sand used for many times have great effect on the quality of the casting. The used sand in the lost foam casting line was investigated. Many basic properties of the used sand such as the distribution of the particles, the amount of dust, the Loss On Ignition (LOI), the permeability, the fluidility and so on were tested. Moreover the properties of the new sand were tested in contrast. The results show that because of more of the coating fragments, more abrasion of sand particles, and more residual thermal decomposition products the properties of used sand become worse, and the reclamation of used sand should be noted in the lost foam casting process.