对比研究了普通一次微波硬化、有机酯硬化、有机酯-微波复合硬化三种水玻璃砂硬化工艺的性能.结果表明,与普通一次微波加热硬化相比,有机酯-微波加热复合硬化工艺可使砂型在微波加热阶段不带模具加热,当有机酯的加入量为水玻璃质量的1.5％时,恒湿瓶中4h存放强度较普通一次微波加热硬化提高了70％；较之于有机酯硬化工艺,有机酯-微波加热复合硬化工艺的水玻璃加入量少、硬化速度快、硬化强度高.进一步系统研究了其他工艺参数(微波加热功率和时间)对有机酯-微波加热复合硬化水玻璃砂型存放强度的影响,并通过扫描电镜观察分析了该工艺下的砂样粘结桥微观结构和硬化机理.%The common sodium silicate sand was cured by microwave heating, the organic ester and the ester-microwave composite process, respectively, and the properties of the sand were analyzed and compared. The results show that compared with the sodium silicate sand cured by microwave heating, the samples cured by ester-microwave composite process could be heated without mold, and when the amount of ester is 1.5% weight of sodium silicate, its 4 h storage strength in the humidistat is increased by 70%; compared with organic ester curing process, the ester-microwave composite curing process has the advantages of shorter heating time, faster curing speed and higher compression strength of the sand. Other factors (the power of microwave and the heating time) influencing the strength of the sodium silicate sand by ester-microwave composite curing were researched. Moreover, SEM was used to investigate and analyze the microstructure of binder bridges and curing mechanism.
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