High temperature heat treatment is one of the main technologies with the highest market conversion rate and broad future prospects in the functional technology of wood. Chemical reagents are not added in the production process. The treatment improves the dimensional stability, biological durability, wood color, and acoustic properties without reducing the environmental performance of the product. However, there are some problems in heat treatment, such as the reduction of mechanical properties and surface wettability of wood, high production energy consumption, and large exhaust emissions. Therefore, understanding the influence and mechanism of high temperature heat treatment technology on wood properties is of guiding significance to further improve the quality of heat-treated wood, improve production process, and develop new equipment. This article reviews the effects of heat treatment on the properties of wood and the mechanism of heat treatment. Then, some applications of heat treatment of wood are introduced. Finally, the development direction and prospect of high temperature heat treatment technology in the future are forecasted.

To improve the color and surface properties of blue-stained radiata pine, heat treatment was carried out at different temperatures and times. The color change, wettability, and dynamic moisture sorption of the wood were investigated. The results showed that, as the treatment temperature and duration time increased, the surface brightness of specimens gradually decreased, and the surface color became more reddish and blueish. In addition, the contact angle of distilled water at 0 s and 18 s gradually increased as the treatment temperature and time increased, which indicated a decrease in the surface wettability. The color of the blue-stained wood became more uniform with reduced surface wettability and hygroscopicity but increased sorption hysteresis after the treatment.