Rapid mold temperature rising method for PEEK microcellular injection molding based on induction heating

Abstract

As a high-performance polymer, Polyether ether ketone (PEEK) and its injection-molded products are widely used as an ideal metal replacement. The production of ideal PEEK injection molded products, including microcellular injection molded, requires the support of high mold temperatures that can be maintained. Given this, a rapid mold temperature rising technology based on induction heating was designed to take advantage of the ultra-high heating rate of induction heating, which effectively met rapid increase and maintenance of high mold temperatures for PEEK injection molding. Both finite element analysis and experimental results showed, compared to the electric heating method, the induction heating method increased the efficiency to 5600% when the mold temperature rise from 150 to 180 °C compared to electric heating. All heating methods were used for the validation tests of injection molding PEEK, microporous injection molding PEEK, and micro-open microporous injection molding PEEK. The experimental results showed that the surface quality of PEEK samples molded by induction heating was 9.8%–61.2% higher than that of the oil heater heating, while the mechanical properties were more than 18%. Besides, the adaptability to longer holding times for micro-open microcellular injection molding suggested it can effectively broaden the possibilities of developing higher-performance PEEK foam products. The pioneering design and analysis of heating methods in this work had important guidance for promoting high-performance polymer injection molding and the lightweight of its foamed products.