【摘要】 采用正交试验对热固化磷酸盐粘结剂砂进行复合改性。结果表明，每份粘结剂中四甲基乙二胺和甘露醇加入量分别为6 g和12 g较优，混砂时阳离子聚丙烯酰胺水溶液和草酸水溶液两种辅料的加入量均为占砂质量0.3%，浓度分别为0.8%和12.5%较优；采用优方案制得的砂样在射砂压力为0.8MPa、模具温度150℃、加热3min的条件下，固化抗弯强度可达4.2MPa，在40%～50%湿度环境下存放24 h，抗弯强度下降幅度为2.83%，试样继续在60%～65%湿度环境下存放24 h后，抗弯强度下降幅度为22.89%，复合改性的热固化磷酸盐粘结剂砂抗吸湿性能有较明显提升。更多还原

【Abstract】 The thermal curing phosphate binder sand was modified by orthogonal test. The results showed that 6 g and 12 g of TEMED and mannitol were better for each binder, the addition amount of both cationic polyacrylamide aqueous solution and oxalic acid aqueous solution was 0.3% of the sand mass, and the concentrations were 0.8% and 12.5%,respectively. Under the conditions of sand shooting pressure of 0.8 MPa, mold temperature of 150 ℃ and heating time of 3 min, the curing flexural strength of the sand sample prepared by the optimized scheme can reach 4.2 MPa,and the flexural strength decreases by 2.83% after storing for 24 h in 40%-50% humidity environment, And the bending strength of the sample continues to decrease by 22.89% after continuously storing for 24 h in 60%-65%humidity environment. The moisture absorption performance of the composite modified thermal curing phosphate binder sand has been significantly improved.更多还原