Characterization of heat treated eastern redcedar (Juniperus virginiana L.)

摘要

The objective of the study is to investigate the influence of heat treatment on shrinkage, density, surface roughness, water absorption, diffusion coefficient, swelling and shear strength of eastern redcedar (Juniperus virginiana L.) samples. The anatomical structures of samples are also observed by scanning electron microscope (SEM). Specimens are exposed to temperature levels of 120℃, 160℃ and 190℃ for time spans of 2 and 8 h. Based on the results of this study, dimensional stability in the form of shrinkage of the samples is improved by 2.68%, 1.40% and 1.49% for tangential, longitudinal and radial grain orientations as function of heat treatment, respectively. Heat treatment also enhances surface quality of the samples based on numerical values determined from stylus type of equipment. Water absorption, swelling values and diffusion coefficient of the samples are also reduced with heat treatment. Samples exposed to heat treatment have lower shear strength values, ranging from 25.12% to 52.67%, than those of control samples. It appears that all properties evaluated in this work are affected more pronouncedly as temperature and exposure time is increased.