湿型砂铸件鼠尾形成机理分析  

Formation Mechanism of Mouse-Tail Defects in Green Sand Mould Castings

作　　者：吴弘[1] 孙广垠[2] 

机构地区：[1]河北工程大学机电工程学院,河北邯郸056038 [2]河北工程大学城市建设学院,河北邯郸056038

出　　处：《铸造》2008年第6期617-619,共3页Foundry

摘　　要：通过理论分析和试验结果表明,液态金属浇注过程中,湿型砂局部型腔表面形成的干砂区受热膨胀,相对于水分凝聚区产生滑移。水分凝聚区在干砂区滑移压力、水蒸气的气体压力和不饱和水分凝聚区的挤压阻力作用下将发生变形而拱起,使铸件产生鼠尾缺陷。水分凝聚区强度下降是鼠尾形成的主要原因。降低型砂含水量,降低型砂膨胀阻力是提高型砂抗鼠尾缺陷能力的主要方法。The theoretical analysis and experimental results showed that during the liquid metal into green sand mold, the local dry sand zone formed on the surface of mold cavity swelled due to be heated and slipped relatively to the moisture condensation zone. Under the action of the slipping pressure n the dry sand zone, vapor pressure and extrusion resistance, the haunch-up in the moisture condensation zone owing to deformation resulted in the formation of mouse-tail. The reduction of strength in the moisture condensation zone was the main cause of the mouse-tail formation, so reducing the water content and expansion resistance of molding sand are the main methods to prevent mouse tail defect from occurring in green sand mold castings.

关 键 词：鼠尾 铸造缺陷 干剪强度 蒸汽压力 水分凝聚区强度 含水量 

分 类 号：TG245[金属学及工艺—铸造] TG21