JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, cilt.26, ss.1421-1429, 2023 (ESCI)
The aim of this study was to determine some physical and mechanical properties of spruce (Picea orientalis) wood, which was impregnated with aqueous solutions of valonia (valex) (the extract of Quercus ithaburensis), pine bark powder (pinex) (Pinus brutia Ten.) and gallnut powder (galex) (Quercus infectoria Oliver) as a pre-treatment and then heat treated. Test specimens were prepared from sapwood of spruce wood and impregnated with 10% tannin solutions before heat treatment base on ASTM D 1413-76. After pre-impregnation processs, specimens subjected to heat treatment at 150 degrees C, 175 degrees C and 200 degrees C for 2 h. The effect of impregnation process and heat treatment temperature on the air-dried density, compressive strength paralell to the grain (CS), bending strength (MOR) and modulus of elasticity in bending (MOE) were analyzed. As results, impregnation solutions showed positive effects on mechanical strength in unheat-treated samples and determined that mecnaical strength loses due to heat treatment slightly limited at low temperatures. However, strength loses increased with increasing temperature. The highest strength loses were also determined in impregnated samples with galex extract and heat-treated samples at 200 degrees C.