【摘要】 <正> 凝固过程是铸造生产中最重要的过程之一,它直接影响到铸件的组织、性能以及缺陷的形成。采用计算机对凝固过程进行数值计算已经成为研究凝固过程的一种重要手段。本文介绍了采用计算机对不锈钢板状精密铸造件的凝固过程进行数值计算的结果。 一、计算方法 铸造过程的凝固现象非常复杂,因此必须根据目的提出适当的模式,然后才能采用计算机进行数值计算。所采用的方法有:有更多还原

【Abstract】 The solidification processes of platelike precision castings of 2.5mm-thick ZG l Cr18Ni9 and 2.5/3.5mm-thick ZG 1 Cr17Ni4 Cu 3 Nb are numerically calculated by direct finite difference method (DFDM) in this paper. The distribution of temperature fields, maximum temperature gradient and maximum solidification time gradient in the castings are found out. It is considered that th critical temperature gradient values of platelike stainless steel with investment castings are roughly 6C/cm2 and that the possibility of shrinkage porosity in some sections of the castings can also be guessed with the aid of maximum solidification time gradient.更多还原