Mechanical Evaluation and XRD/TG Investigation on the Properties of Wooden Dowel Welding

Abstract

Mechanical properties related to wooden dowel welding were studied using five different moisture content (MC) values. Birch wooden dowels and Chinese larch substrates were used in this study. A 2% MC for the wooden dowels and a 12% MC for the substrates resulted in the highest pullout resistance. A fitting analysis showed that there was a linear relationship between the pullout resistance and the different values of MC. The errors between the calculated values and the test values were less than 10%. The pullout resistance of the wooden dowel welding fit a Weibull distribution. No accurate linear relation existed between the 95% reliability pullout resistance and the different MC values. Chemical analyses were performed separately on the wooden dowel and the welding interface of a wooden dowel sample with 2% MC and a substrate with 12% MC. X-ray diffraction (XRD) analysis revealed that the degree of crystallinity of the welding interface was 75% higher than that of the wooden dowel. Finally, thermogravimetric analysis (TG) illustrated that pyrolysis of the wood components occurred during the wooden dowel welding process.