超声波对铸造水玻璃砂性能的影响

Effects of Ultrasonic Wave on Properties of Cast Sodium Silicate Sand

水玻璃砂在混制后会出现老化现象,从而降低其强度、溃散性、抗吸湿性等。把模数为2.6左右的水玻璃放在频率为20kHz、功率为480W的超声波处理器中进行改性处理后测试其相关性能。结果发现,水玻璃的粘度随超声处理时间的延长不断降低,在30min时水玻璃粘度降低11%,水玻璃的润湿性较改性前提高13%~37%;水玻璃砂的干强度增幅达到48%;同时,水玻璃砂的高温残留强度下降41%;水玻璃在超声改性前后混制得到的水玻璃砂的抗吸湿性提高8%。结果表明,超声波处理可以提高水玻璃砂的强度和抗吸湿能力,同时能够提高型砂的溃散性。

Due to aging of sodium silicate sand after mixing,it can reduce its strength,collapsibility,moisture resistance and so on.Sodium silicate was modified in an ultrasonic processor with a frequency of 40 kHz and a power of 480 Wto test its performance.The results show that the viscosity of sodium silicate is decreased with the increase of ultrasonic treatment time.At 30 min,the viscosity of sodium silicate is decreased by 11%,and the wettability of sodium silicate is increased by 13%~37% compared with that of ones before modification.The dry strength of sodium silicate sand is increased by 48%.At the same time,the residual strength of sodium silicate sand at high temperature is decreased by 41%,and the hygroscopicity of sodium silicate sand prepared by mixing sodium silicate sand before and after ultrasonic modification is increased by 8%.The results show that ultrasonic treatment can improve the strength and hygroscopicity of sodium silicate sand,and improve the collapsibility of moulding sand as well as reducing the amount of sodium silicate.