<i>Tectona grandis</i>: Examine an Ultrastructure on Cultivated Teakwood due to the Scanning Electron Microscopy Enhanced by Heat Treatment

Abstract

Cultivated timber species that focus on fast-growing are slowly being utilized as an alternative source of materials by the timber industry worldwide. Most of them are cultivated as mono-species and, upon harvesting, possess lower properties than those harvested from the forest. To utilize them for a longer service span requires preservatives or some other treatment. The environmentally friendly heat treatment process can improve the wood properties by improving their durability against insects and fungi attacks. Each species requires optimum temperature and treatment duration without affecting its properties. Applying the heat treatment at extreme temperatures and duration can reduce the strength properties. This paper investigated the ultrastructure of heat-treated cultivated 10- and 15-years-old Tectona grandis after a three-month grave ground contact test. A Scanning Electron Microscope (SEM) was used in the investigation. The correlations were drawn between the treated and untreated teak before and after three-month periods. The inspections concentrate essentially on the cell structure changes due to the heat treatment process. No significant difference was observed between the two age groups. However, heat-treated samples at extreme temperatures experience elongated and collapsed vessels, deformed fibers, and decreased microfibrils in the cell walls of fibers. The study intimates that heat treatment alters the cell structure of cell walls in teak wood and increases the durability of the wood in the long term.