Physicomechanical and Morphological Structure Analysis on the Oil-heat Treated 10 Years Tectona grandis

Abstract

This paper examined properties that focussed on the microphotographs structure, physical properties, and mechanical characterization of the heat-treated 10-year-old cultivated Tectona grandis wood. The harvested wood was subjected to the heat treatment process at 160°C, 200°C, and 240°C for two hours in an electrically powered oil heat-treatment machine. The heat-treated and the control untreated samples were subsequently exposed in the two (2) years grave-yard tests ground. Selected teak wood was taken out after undergoing a certain period of testing. Moreover, the physical properties, such as the moisture content, maximum density, basic density, and volumetric shrinkage were determined. The mechanical properties were assessed using static bending and compression tests focusing on the modulus of elasticity (MOE) and modulus of rupture (MOR). The physicomechanical test was carried out according to the ASTM standard.  The study revealed that the oil heat-treatment process altered the cell structure of the teak wood, particularly at those exposed to elevated temperatures. Changes were observed in the fibre and parenchyma cells of the wood, and the heat treatment process generally improved the properties of the wood, particularly in the physical properties. The Scanning Electron Microscope (SEM) was used to study changes in the wood's anatomy and microstructures especially on treated, untreated, and ground test samples. The study results showed that the oil heat-treatment process improved the durability of teak wood against wood-decaying fungi. Nonetheless, extreme heat treatment temperatures altered the teak wood's cells’ structure, leading to reduced strength in the cell walls but at an acceptable level.