一、引言水玻璃作为砂芯粘结剂在50年代初期应用于铸造生产中。它具有来源广、价格低、无毒性、水溶性、长期贮存的稳定性等宝贵性能。以水玻璃为粘结剂的型(芯)砂混制非常方便,易于充填芯盒;可吹CO_2气体硬化,加入硬化剂自硬和热空气硬化等;节约能源,缩短生产周期,利于连续生产。水玻璃砂的主要缺点是铸型和砂芯的溃散性差,旧砂不易回用,使铸件落砂(打箱)费用增加,劳动条件恶化,而且对铸件收缩起阻碍作用,导致铸件 I. Introduction Water glass as a sand core binder in the early 1950s used in casting production. It has a wide range of sources, low prices, non-toxic, water-soluble, long-term storage stability and other precious properties. Water glass as the binder type (core) sand mixing is very convenient, easy to fill the core box; blowing CO_2 gas hardening, adding hardener and hot air hardening, etc .; energy conservation, shorten the production cycle, which will help continuous production . The main drawback of sodium silicate is the collapse of the mold and the sand core is poor, the old sand is not easy to reuse, so that casting sand (boxing) costs increase, deteriorating working conditions, but also impede the casting shrinkage, resulting in casting