Wood in outdoor applications undergoes various degradation processes such as biological degradation as well as weathering. However, since carbon black is a very effective photostabilizer, it is hypothesised that wood surfaces can be protected from weathering by a layer of carbon (charcoal). Norway spruce (Picea abies) samples were pyrolised to create carbonised layers of varying thickness and exposed to artificial weathering for eight weeks.To investigate surface changes due to weathering, colour measurements and ATR FTIR measurements were made. The results show that carbonised surfaces protect wood from weathering but they also undergo chemical changes. Thus, the thickness of carbonised layers influences the weathering protection of wood.

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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.