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Abstract

Silicone/phosphor composite is a functional material used in light-emitting diode packages. In this paper, Young’s modulus of silicone/phosphor composite is studied experimentally and investigated with a multi-sphere random unit cell model. Experimental samples of pure silicone and four groups of silicone/phosphor composites are prepared and subjected to tensile loading. Young’s moduli of the samples are calculated from tensile curves. The results indicate that composite modulus increases with increasing content of phosphor, and silicone matrix is stiffened by the phosphor particles. In the simulation part, unit cell model is utilized and serves as the statistical representation of the original composite. The employed three-dimensional random unit cell model consists of silicone matrix and randomly dispersed phosphor particles with various sizes. Modeling results from random unit cell model are compared with experimental results and theoretical predictions. It is found that, with increasing volume fractions of phosphor, random dispersion and size variation of phosphor have increasingly significant influence on homogenized Young's modulus of silicone/phosphor composite.

Keywords

Functional composite mechanical property multi-scale modeling probabilistic method

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Estimation of homogenized Young’s modulus of silicone/phosphor composite considering random dispersion and size variation of phosphor particles

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