EXPERIMENTAL STUDY ON THE EFFECT OF THERMAL DRYING ON THE MECHANICAL PROPERTIES OF WOOD

Drying is a complex operation involving transient transfer of heat and mass along with several rate processes, such as physical or chemical transformations, which in turn, may cause changes in product quality. This article surveys the impacts of convective, infrared and microwave drying on the strength of dried wood. The effects of drying methods on mechanical properties have been studied for many materials, but wood products have seldom been the subject. Spruce wood samples (length = 140 mm and diameter = 21.mm) were dried using the following drying regimes: convective (100 ْ C and 40 0C.), microwave (480, 790, and1000 W power) and infrared (100% power). The dried samples were then subjected to tensile loading in order to evaluate the mechanical properties. It is concluded that the microwave drying can improve the strength of dried samples significantly.

Keywords:

Thermal drying , wood , mechanical properties