Shape Stability of Particleboards Covered with Decorative Veneers

This paper summarizes the results of research aimed at determining the shape stability, modulus of rupture (MOR) and modulus of elasticity (MOE) of components made of particle boards, covered on their front side with decorative veneer of American walnut (Juglans nigra), 0.6 mm thick, and on the underside with decorative veneers of other species (Picea abies and Fagus sylvatica), 0.6–1.5 mm thick, or by a countermove foil of 85–90 g/m2 surface weight. Subsequently, measurements were carried out of the shape stability (warping) of test specimens cut from various combinations of surface-finished boards. These test specimens were air conditioned in three different environments. At the same time, values were determined of bending strength and modulus of rupture with respect to the direction of fibres of sheathing materials. It has been found that the lowest warping values were achieved with combinations consisting of American walnut of a thickness of 0.6 mm on the tight side and alder (Alnus glutinosa), 0.6 mm thick, on the underside.