Guidelines for the Rough Machining of Die Casting Dies

摘要

Die casting dies are normally rough machined with the steel in the annealed condition, with finish machining being performed after heat treatment. However, during the heat treatment process the die goes through a metallurgical transformation that generates stresses and a permanent distortion of the tool. Features machined into dies (such as sharp internal radii) can significantly increase stress levels developed in a die during quenching, with the possibility of causing gross cracking of the tool. A short booklet soon to be published by NADCA~((1)) offers principles for rough machining, to provide information to die casters and tool shops to ensure that features machined into the die during rough machining will not cause problems during heat treating, and that sufficient stock is left on the die so that it can be machined to finished dimensions after heat treatment. This paper will summarize information from that booklet.