铸造生产中硅砂的选用

介绍了硅砂的膨胀相变特性及其与各种铸造缺陷的关系。叙述了铸造用硅砂的物化性能要求,包括SiO2含量、粒度分布、表面形貌、表面洁净度等。说明了不同用途的原砂的选用原则:包括铸钢用砂,铸铁用砂,铸铜、铸铝用砂,V法用砂,消失模及实型用砂,树脂自硬砂,覆膜砂用砂等。最后指出,铸造用砂应根据铸件种类、铸件大小、铸型类别、工厂生产条件,就近合理选用原砂;人造硅砂易破碎、复用性差,除一次性用砂的水玻璃型和厚大铸件使用外,尽量慎用。

Selection of Silica Sand Used for Foundry Production

The expansion phase transformation characteristics of silica sand and their relationship with various casting defects were introduced.The physical and chemical properties requirements of foundry-used silica sand were described including content of SiO2,grain size distribution,surface morphology,surface cleanness etc.The selection principle of raw sand used for different purpose was explained：including steel casting production-used sand,iron casting production-used sand,copper and aluminum alloy casting production-used sand,V-process-used sand,EPC process-used and full-mold-used sand,resin selfsetting process-used sand,and sand for resin-coated sand,etc.It was pointed out finally,that the foundry-used sand should be rationally chosen in nearby area according to the casting sort,casting size,mold sort and production conditions of the foundry; since the artificial silica sand is easy to be broken,its reclamation possibility is poor,therefore it should be used cautiously with exception to be used as one-off sand for the sodium silicate-bonded sand and heavy steel casting.