Production processes, material properties and applications of densified wood: an overview.

The increase in demand and the acute supply of good quality wood has created a gradual shift towards fast-growing species with low to medium-strength properties. Modification methods are often necessary to improve the properties of such timbers thereby expanding their application potential. As the mechanical properties of wood are strongly dependent on its density, artificially increasing the density is a good wood modification strategy for quality enhancement. Wood densification helps improve the mechanical properties of low to medium-density woods with limited structural applications in building and construction. The structure of the wood changes when the porosity is reduced through impregnation with chemicals, mechanical compression or their combination, thereby increasing the density and altering the material properties. The mechanical densification of wood follows three basic steps i.e., plasticisation, compression and fixation of the deformed or densified stage. The different processes adopted for wood densification have been described in this paper. The properties of densified wood are dependent on the process parameters such as pressure, temperature, treatment duration and the densification method used. The properties of the densified wood, their applications and future areas of research are also explored in this review. [ABSTRACT FROM AUTHOR]