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DOE OSTI · 22038674

Void evolution in polycarbonate at elevated temperatures

Chen, Y H·Li, C L·Lee, Sanboh·Chou, Kuo Feng
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Abstract

The void evolution in polycarbonate (PC) at elevated temperatures was investigated. Internal cylindrical cracks and voids were induced in PC by Nd-YAG laser irradiation. During the annealing at temperatures of 177-197 deg. C, the spherical void grows to a maximum size, which then decreases, and is finally leveling off. A model of void evolution based on the evaporation and condensation mechanisms for growth and shrinkage is proposed. The theoretical predictions are in good agreement with the experimental data. The activation energies of evaporation and condensation processes are determined to be 477.31 and 611.49 kJ/mol, respectively.

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36 MATERIALS SCIENCEACTIVATION ENERGYANNEALINGCRACKSCRYSTAL GROWTHCYLINDRICAL CONFIGURATIONEVAPORATIONIRRADIATIONLASER RADIATIONNEODYMIUM LASERSPOLYCARBONATESSHRINKAGESOLIDSSPHERICAL CONFIGURATIONVOIDS

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Chen, Y H, Li, C L, Lee, Sanboh, Chou, Kuo Feng. 2011-08-15. Void evolution in polycarbonate at elevated temperatures. https://doi.org/10.1063/1.3622673

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36 MATERIALS SCIENCE↗