Effect on the Residual Stress of Cure Profiles, Fillers and Mold Constraints in an Epoxy System

  • Moon, Chang-Kwon (Pukyong National University, Division of Materials Science and Engineering) ;
  • Nam, Ki-Woo (Pukyong National University, Division of Materials Science and Engineering)
  • Published : 2009.08.31

Abstract

A dilatometer was used to investigate the effect of cure conditions, mold types and the presence of filler in an epoxy system. These studies showed shrinkage in the cured epoxy when heating it through the glass transition temperature region. The magnitude of the shrinkage, related to stress build up in the epoxy during curing, was influenced by the processing conditions, filler presence and the nature of the mold used to contain the resin. Cure and cyclic cure at a lower temperature, prior to a post cure, decreased the magnitude of observed shrinkage. Cure shrinkage decreased with the number of cyclic cures. Post cured samples outside the mold led to less shrinkage compared with samples in the mold. Sample cured in a silicon mold represented less shrinkage than sample cured in an aluminum mold. Sample containing kaolin filler showed less shrinkage than unfilled sample.

Keywords

References

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