Pelit, HüseyinYorulmaz, Ramazan2020-04-302020-04-3020191930-2126https://doi.org/10.15376/biores.14.4.9739-9754https://hdl.handle.net/20.500.12684/3362WOS: 000493997400153The effects of mechanical densification on density, Brinell hardness, bending strength (MOR), modulus of elasticity (MOE), and compression strength (CS) of thermally pretreated spruce (Picea orientalis) and poplar (Populus nigra) wood samples were investigated. Thermal treatment was applied on the wood samples at four different temperatures (140 degrees C, 160 degrees C, 180 degrees C, and 200 degrees C) and two different durations (7 h and 9 h) under atmospheric pressure. Wood samples were then densified by compression at a temperature of 150 degrees C to two degrees (20% and 40%) of compression. The results indicated that the density, hardness, and MOR values of both compressed and non-compressed thermally pretreated spruce and poplar samples decreased with increasing treatment temperature and duration. At temperatures below 200 degrees C, the MOE was generally increased in thermally pretreated samples. However, the MOE was reduced in thermally pretreated samples at 200 degrees C compared to the untreated samples. Additionally, all thermal pretreatments increased CS values in compressed and non-compressed wood samples. The CS tended to decrease in thermally pretreated samples (especially 40% compressed) at 200 degrees C. After the densification, all of the strength properties tested in thermally pretreated samples increased significantly depending on the increase in compression ratio.en10.15376/biores.14.4.9739-9754info:eu-repo/semantics/openAccessDensificationHardnessMechanical strengthThermal treatmentWood materialArticle14497399754WOS:000493997400153Q3Q2