Effects of steaming treatment on the technological properties of olive wood

Wood modification is a process that alters the properties of wood through chemical, thermal, or physical treatments, thereby improving its performance, including durability and dimensional stability. Steaming is a hygrothermal treatment that can modify physical properties and may affect mechanical performance depending on process severity. This study investigated the effects of low-temperature steaming on olive wood (Olea europaea L.) by applying a constant temperature (80 °C) and varying treatment duration (12, 18, and 36 h) compared with natural seasoning (control). Color and dynamic modulus of elasticity (MOEd) were measured on boards before and after treatment; after, specimens were tested for dimensional stability, bending properties (MOR and MOEs), compression strength, Janka hardness, and abrasion resistance. Steaming produced significant color changes in both heartwood and sapwood, with stronger responses in sapwood. Bending properties showed non-significant increasing trends, with mean MOR increasing from 50.21 MPa (control) to 62.24–64.71 MPa and the highest mean MOEs observed in the 12 h group (+ 13.45% vs. control). Compression strength was comparable to the control (56.34–57.77 MPa). Janka hardness showed a decreasing tendency (up to − 21.3% in the 12 h group), while abrasion weight loss increased slightly and differed significantly among groups (0.21% in control vs. 0.24–0.29% after steaming). Overall, low-temperature steaming at 80 °C appears suitable for improving olive wood color uniformity and selected technological performance while limiting the mechanical degradation typically associated with high-temperature thermal modification.