Effects of heat treatment and surface roughness on bonding strength

The objective of this study was to determine the effect of heat treatment on bonding strength of the samples from four different species, namely Scotch pine, oriental beech, white oak and Uludag fir woods. The samples were exposed to three temperature levels of 120 °C, 150 °C and 180 °C for time periods of 2 and 6 h. Based on the findings in this work white oak samples had the highest average roughness (Ra) and maximum roughness (Rmax) values of 9.49 μm and 48.9 μm, respectively. It appears that heat treatment enhanced overall surface quality of the samples.

► Bonding strength of the heat-treated samples were lower than those of control samples.
► It seems that heat treatment had a limited benefit on surface roughness of the samples.
► Heat treated samples are not recommended for structural use.