【摘要】 本文认为采用冷却面积扩大法设计外冷铁方法简单、实用,数值计算法从铸件凝固角度揭示了铸件内部组织和缺陷形成的本质,计算精度高.如将两者结合起来,可成为一种较完整的既可靠又实用的外冷铁工艺设计技术.通过实验数据阐明了诸工艺因素,如铸件-冷铁间挂砂层厚度、冷铁厚度、铸件壁厚、铸件与冷铁间接触条件等,对冷却面积扩大系数K和铸件-冷铁间界面换热系数h两个参数的影响及规律.更多还原

【Abstract】 The cooling surface enlargement method for designing the external chills is considered to be simple as well as practical, while the numerical method for calculating the casting solidification reveals the essence of casting structure and defect formation and has higher accuracy. If combining the two methods, it becomes more reliable as well as practical for designing the external chills.The experimental results have demonstrated the influence of technologi-cal factors, including sand layer thickness between the casting and the chills, chill thickness, wall thickness of castings and the contact conditions of the casting-chill interface, on the cooling surface enlargement coefficient K and the heat exchange coefficient at the casting-chill interface h and its regulation.更多还原