Three-Dimensional Finite Element Analysis of the Induction Heating Procedure of an Injection Mold

Abstract

Rapid mold heating has been recent issue to enable the injection molding of thin-walled parts or micro/nano structures. High-frequency induction is an efficient way to heat mold surface by electromagnetic induction in a noncontact manner, and has been recently applied to the injection molding due to its capability of rapid heating and cooling of mold surface. The present study covers a three-dimensional finite element analysis to investigate heating efficiency and structural safety of the induction heating process of an injection mold. To simulate the induction heating process, an integrated simulation method is proposed by effectively connecting an electromagnetic field analysis, a transient heat transfer analysis and a thermal stress analysis. The estimated temperature changes are compared with experimental measurements for various types of induction coil, from which heating efficiency according to the coil shape is discussed. The resulting thermal stress distributions of the mold plate for various types of induction coils are also evaluated and discussed in terms of the structural safety.