Technical Note: Effect of Epoxy Embedment on Micromechanical Properties of Brown-Rot-Decayed Wood Cell Walls Assessed with Nanoindentation


  • Jae-Woo Kim
  • David P. Harper
  • Adam M. Taylor


Brown-rot decay, softwood, nanoindentation, resin embedding


Mechanical properties of brown-rot-decayed wood cell walls were evaluated using a nanoindentation technique. Epoxy resin is a typical medium for the sample embedding process in nanoindentation. It is assumed that the embedding process does not affect cell wall properties or that any effects are similar for different samples. As part of an investigation of microscale mechanical effects of brown-rot in wood, we applied nanoindentation to cell walls of decayed and nondecayed pine wood samples. For epoxy-embedded samples, there were no differences in modulus and hardness for control and decayed samples. However, for unembedded samples, significant differences were found between control and decayed samples. These results indicate that the epoxy-embedding process may confound micromechanical testing results. We speculate that in this case, epoxy resin penetrated and reinforced the cell wall of decayed samples.


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