Introduction of shock wave technology to fir wood preservation

Abstract

Similar to a normal wave, a shock wave travels as energy through matter but it causes an abrupt rise of pressure, temperature and density. In this study, the influence of shock waves on wood structure were investigated in the light of possible future industrial utilization e.g. timber impregnating treatment. The constructed autoclave is capable of creating shock waves either by an electrical pulse breakdown of a spark gap arrangement or by electromagnetic actuators. The penetration depths of the fir wood test samples were measured using light microscopy, SEM and micro-computed tomography. Our results showed that by varying the intensity of the incident shock wave, the distance between the shock wave generating device and the test sample, and/or the orientation of test sample in relation to the shockwave, the wood tissue structure had been heavily disintegrated or hardly affected at all. An improvement on impregnation could not be found.