Effects of process parameters on core-back foam injection molding process

摘要

Experiments of a new core-back foam injection molding process are described in this paper wherein the blowingagent content [%], mold temperature [°C], shot size [mm], injection speed [mm/s], holding pressure [MPa], holding time [s]and core-back rate [mm/s] were taken as single variables, respectively. The effects and mechanisms of the above parameterson the molding process were studied. The relationships of the parameters with the mechanical properties and the weight reductioneffect of the specimens were analyzed. The results show that the effect of blowing agent content, mold temperature,shot size, injection speed and core-back rate in the new method is similar to that of conventional core-back foam injectionmolding. However, the first stage holding pressure and holding time of the holding process in the secondary filling stagewhich the new method peculiarly possesses play the same role as shot size and injection speed in conventional foam injectionmolding, and the second stage holding pressure and holding time play the role of pressure holding in conventional foam injectionmolding. Compared with the conventional foam injection molding method, the specimens obtained by using the newmethod have higher weight loss rate, better mechanical properties, and higher specific strength.