Development of a thermo-hydro-mechanical device for wood densification adaptable to universal testing machines and its evaluation in a tropical species

There is considerable interest in the development of thermo-hydro-mechanical (THM) treatments to increase the density of low-density woods. However, the development of processes for improving the properties of low-density woods in regions with lower investments in investigations and development, such as tropical areas, is often limited by the equipment and infrastructure constraints. The aim of this work is to outline the development and construction of an inexpensive THM densification device (THM device) that controls the application of heat, load, and steam, by adapting an accessory to a 60-Mg universal testing machine (UTM). The THM device was evaluated using the Vochysia guatemalensis wood (tropical species). The inexpensive densification THM device uses steaming, temperature, and compression and can be adaptable to a 60-Mg-capacity UTM. It also allowed us to successfully conduct the densification process on 20 by 70 by 300 mm wood samples of a low-density tropical species. However, there were some drawbacks discovered: for example, the steam application, pressure, and temperatures were controlled independently, which was not convenient. It would be more convenient to concentrate them in a single control unit. Additionally, a high variation was observed in the compression and stabilization thickness.