原砂对新型改性水玻璃型砂溃散性的作用机理

研究了原砂对水玻璃型砂溃散性的影响；通过扫描电镜观察了水玻璃型砂高温焙烧后的粘结桥形状和砂粒表面特征，用电子探针和X射线衍射分析了砂粒表面膜的主要生成物的成分和形态，揭示了不同品位的石英砂与水玻璃粘结剂发生高温反应后残留强度高低不同的原因．研究结果表明，都昌砂高温下与水玻璃反应生成了高熔点的蜂窝状钾长石，导致型砂的残留强度很低；而海城砂则生成了低熔点的物质，使得型砂的残留强度很高．因此，改变石英原砂的表面状态是提高水玻璃型砂溃散性的一个有效途径．

The effect of quartz sand on collapsibility of modified sodium silicate bonded sand

The appearances of surface and neck of bonded sand ba ke d at high temperature in sodium silicate bonded sand were observed by SEM, and t he configuration and component of surface film of sand baked were analyzed by el ectron probe and X-ray diffraction. The reason why the remained strength was va ried when sodium silicate binder reacted with different quality quartz sands at high temperature was found. It was shown that the remained strength of sodium si licate bonded Duchang sand was lower because honeycomb-like high melting point kali-feldspar was produced and the remained strength of sodium silicate bonded Haicheng sand was higher because easy melting substances was produced after sand reacting with sodium silicate at high temperature. To change appearance of san d was effective to improve collapsibility of water grass bonded sand.