模具结合面的空气隙形成处理和间隔处的换热机制

中文字数:3504,中文页数:7 英文字数:2626页数:9

 铸件模子交接面工序系统的空隙和缺口传热机理是通过测量位移和圆柱的和平面铝合金铸件温度测定的。空隙的厚是测量铸造表面和内表面轮廓之间的区别。对于圆柱状管型，开始向外移动后立即倾倒直到凝固基本发生时；对于平面铸件，倾倒后模子开始的移动大大多于铸件，在工件最大厚度出现后相对移动。可以从热膨胀计算出模子的位移。当空隙的厚度不大的时热量主要通过间隙进行热传递。
一 介绍   容易和迅速的做出最适当的铸造设计是铸造工程师进行研究的重点。近年来、计算机模拟程序正在积极地发展到模拟凝固的铸件模子里。信息被用于这个模拟主要是尽可能精确地预知铸件缺陷。至于镶铸的凝固金属型凝固的发展大大地依赖铸件交界面传热系数和它的时间关系。如果空隙在模子铸件交界面是在凝固期间成形的，传热系数将飞快的减少。因此，一部分铸件的温度由于热量的局部流动可以上升。

 The formation process of the air gap at the casting-mold interface and the heat transfer mechanism through the gap were investigated by measuring the displacement of, and the temperature in casting and  mold  for cylindrical and  flat castings  of aluminum  alloys.  The thickness  of the  air gap  was measured as the difference between the location of the casting  surface and that of the mold inner surface. For cylindrical castings, the mold began to move outward immediately after pouring, while the casting stayed until solidification progressed to a great extent. For flat castings, the mold began to move greatly toward the casting pushing the casting immediately after pouring and moved reversely after a maximum appeared.  It was  possible to calculate the displacement of the  mold by thermal expansion. It was found that when the thickness of the air gap was not large, the heat through the gap was transferred mainly by heat conduction.