聚乙烯醇——水泥自硬纱是目前国内外铸造生产中首创的一种新型造型、型芯自硬砂。它由原砂、水泥和聚乙烯醇按一定比例配制而成。南京工学院、上海机械工艺研究所自1976年开始就对该自硬砂进行深入的研究和初步试用,由于配合采用了特制的B——1脱模剂和聚乙烯醇自干涂料,解决了粘模问题,并不需要烘烤,使该自硬砂获得了成功的应用。浙江锻压机床厂1982年开始进行了一年多的生产应用研究,摸索出一套工艺方法,浇注出一百多吨合格的灰铁铸件。生产实践表明:该自硬砂强度和表面强度高,溃散性和出砂非常优越,原砂品位无特殊要求, Polyvinyl alcohol-cement self-hardening yarn is a new type of molding and core self-hardening sand that is firstly introduced in the casting production at home and abroad. It is prepared from raw sand, cement and polyvinyl alcohol in a certain proportion. Nanjing Institute of Technology and Shanghai Institute of Machinery Technology have conducted in-depth research and preliminary trials of this type of self-hardening sand since 1976. The use of a specially formulated B-1 release agent and polyvinyl alcohol self-drying coating has been solved. The sticking problem does not require baking, so that the self-hardening sand has been successfully applied. Zhejiang Forging Machine Tool Factory began its production and application research for more than one year in 1982, and found a set of process methods to cast more than 100 tons of qualified gray iron castings. The production practice shows that the strength and surface strength of the self-hardening sand are high, the collapsibility and sand production are very superior, and the original sand grade has no special requirements.