ANALYSIS OF AN INDUCTIVELY HEATED COMPRESSION MOLDING PROCESS

Compression molding of high viscosity polymeric powders is a character istically slow processing method. This article analyzes direct inducti on heating of the compression molding die, instead of heating by condu ction via the press platens. Applying heat directly to the die near th e polymer, decreases the processing time significantly and, improves p rocess control by reducing thermal mass and response time. Analysis of the electromagnetic field and transient infrared photography resulted in an understanding of the heating pattern of the die. These results were used in a finite element model of the process to predict the temp erature history of the die and polymer. The parts made using this proc ess were compared with parts made with conventional processing methods using thin-film tensile testing, density gradient column testing, and microstructural investigation of the degree of consolidation of the p owder particles. The methods used to analyze this processing technique and tooling can provide process and mold designers with significant i nsight. (C) 1998 John Wiley & Sons, Inc. Adv Polym Techn 17: 251-257, 1998.