铸造生产中硅砂的选用

Selection of Silica Sand Used for Foundry Production

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。

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.