Hot warpage of LCP(Liquid Crystalline Polymer)injection molded part used hot environment is strongly influenced by anisotropy generated by shearing strain in injection molding process. Therefore the analysis of the flow-solidification process in the mold becomes important to analyze the anisotropic distribution of the part. However, the conventional speed distribution measurement such as PIV and temperature distribution measurement such as integrating thermocouple are difficult in LCP. In this paper, we suggested the experiment analytical method that combined measurement of the capacitance between the electrode on mold with electric field analysis and flow analysis to get permittivity distribution focusing temperature dependency on permittivity of LCP. With this method, we analyzed the difference of the flow course and a difference by the flow head after the passage about the flow-solidification behavior in the mold. In addition, we discussed a heat transfer coefficient as a parameter about a change of the time when flow solidification was completed. Then, we assessed difference between measurement and analysis for flow-solidification behavior of the whole mold cavity. As a result, the following points were obtained;
(1) The behavior of the capacitance by analysis simulates the behavior of the experiment qualitatively. Therefore, this experimental analysis method is applicable to thin-wall LCP injection molding.
(2) The estimation of the heat transfer coefficient of the mold cavity surface is enabled by finding a condition to synchronize cooling time for measurement and analysis.
(3) It is necessary to consider the shear heat generation and the distribution of heat transfer coefficient exactly in flow analysis to reproduce solidification behavior of the whole injection molded part.
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