水玻璃旧砂的力学性能及其可再生性

Mechanical properties and reclaimable capacity of used sodium silicate sand

提出了通过计算水玻璃旧砂残留粘结剂膜的弹性模量/屈服压应力的比值大小来衡量水玻璃旧砂的可再生性的准则,即比值越大,旧砂的可再生性越好;通过试验测试了不同处理温度下水玻璃砂样的屈服压应力和弹性模量,用来反映水玻璃旧砂残留粘结剂膜的力学性能.试验结果表明:加热条件下,受热温度为320~520℃时,水玻璃砂样的弹性模量/屈服压应力的比值较大,"加热-机械"再生效果较佳;冰冻温度为0^-40℃时,水玻璃旧砂的冰冻温度越低越有利于再生,且水玻璃砂样中的含水量对水玻璃砂样的弹性模量/屈服压应力的比值影响较大,当含水量为5%~15%时,"冰冻-机械"再生效果较好.

The reclaimable capacity of used sodium silicate sand can be tested after its elastic modulus/ yield compression stress ratio of residual binder film are calculated. The ratio bigger, the reclaimable capacity of used sand is better. And it was tested the mechanical property of sodium silicate sand sample under different processing temperature, which was used to reflect the mechanical property of the residual binder film of the used sodium silicate sand. The results showed the elastic modulus/yield compression stress ratio of the sand sample under different conditions. Under heating condition, the elastic modulus/yield compression stress ratio of sand sample is bigger when the heating-up temperature is 320-520℃, so the effect of ＂heating-mechanical＂ reclamation is better. When the freezing temperature is 0--40 ℃, the lower freezing temperature is better for the reclamation of used sand, and the water content of sand sample has great impact on the elastic modulus/yield compression stress ratio. The ＂freezing-mechanical＂ reclamation effect is better when the water content is 5 %-15 %.