No abstract

No abstract

Correcting and quickly predicting the shrink mold shape in the sport shoe industry for direct injection-expanded foam molding manufacturing procedures are critical. Traditional methods rely on the engineer to guess the initial shrink mold shape when manufacturing the actual shrink mold and shoe sole product. The artificial experience is then used to compare the original large 3D model with the shoe sole product to modify the shrink mold, requiring numerous iterations to complete. In this study, we designed a series of rectangular specimens varying with z-thickness, and measured the density in the middle location of these specimens and transferred them into an expansion ratio. Furthermore, we performed a heat transfer simulation to determine the temperaturetime curve in these locations and correlated the expansion ratio with the curve. We then used the heat expansion finite element method to simulate the expansion behavior. Finally, we used the actual shoe sole to verify our algorithm; with the precision meeting the shoe sole requirement. Therefore, this algorithm can reduce the number of iterations.

A laser based surface scanning technique was utilized to measure the polyimide coated silicon wafer curvature resulting from thermal cycling and mismatch, Meanwhile, mechanical properties of polyimide thin film were characterized by DMA, TMA and tensile test. Based on the obtained material properties, A FEA model was developed to analyze the experimental results -reasonable correlation was obtained.Similar approaches were taken one step further in the MCM silicon substrate curvature measurement. In a MCM package with silicon substrate, epoxy adhesive, and ceramic package, substrate warpage was developed in a thermal cycle due to thermal mismatch between the substrate and the package and coupling effect linked by epoxy adhesive. Three different substrate curvature measurement techniques were applied to identify the substrate curvature and epoxy thin film properties were also well characterized. A 3D FEA model incorporating with the epoxy material properties was developed to analyze the substrate warpage and investigate an optimal package design.

No abstract