不同受热温度下水玻璃旧砂的性能特征

Performance Character of Used Sodium Silicate Sand Under Different Temperature

对不同受热温度下水玻璃旧砂粒上残留粘结剂膜的物理形貌及力学性能进行了较系统的试验研究。模拟试验的结果与砂样试验的结果基本吻合,320℃～520℃温度区间上,水玻璃旧砂的残留强度最低。由于这个温度区间的粘结剂膜的物理形貌也呈现许多大小不同的孔洞,加之这个温度区间上干法再生砂的可使用时间基本上接近于新砂。因此,对水玻璃旧砂进行再生前,对其进行320℃～520℃的加热,可以显著提高干法再生的效果。

The physical pattern and mechanical property of residual binder film on the used sodium silicate sand under different temperature were studied by the numbers. The results of the analog experiment are coincident with the sand sample experiments. The residual strength of the used sodium silicate sand is lowest under 320℃ -520 ℃. And the physical pattern of the binder film presents many bigger or smaller holes under the same temperature. Further more, the bench life under the same temperature is near that of the raw sand basically. Therefore, that used sodium silicate sand was heated under 320 ℃-520 ℃ before reclaiming would improve the effectiveness of the dry reclaiming greatly.