METHOD FOR FORECASTING MOLDING SHRINKAGE RATE OF INJECTION-MOLDED ARTICLE

摘要

PPROBLEM TO BE SOLVED: To provide a method for forecasting a molding shrinkage rate of an injection-molded article, which reduces the number of trial fabrications after manufacturing a die, by estimating a right shrinkage rate before designing and creating the die. PSOLUTION: A distribution of volume shrinkages in a molded article is found by a flow analysis, and a birefringent degree which is an index of a molecular orientation strength is found by a remaining stress analysis. A relation between the birefringent degree and a mold shrinkage anisotropy is actually measured. An amount of the mold shrinkage of the molded article and a distribution of shrinking directions are forecasted by sorting the volume shrinkage rate to the mold shrinkage rate in each direction so that the molded article distribution of the volume shrinkage rate in the molded article tiny region found by the analysis, based on the measured data, is squared with the shrinkage anisotropy actually measured according to the distribution of the volume shrinkages obtained by the analysis. PCOPYRIGHT: (C)2007,JPO&INPIT