Influence of steam pressure on physical and mechanical properties of heat-treated Mongolian pine lumber

An initial study was carried out to compare the physical and mechanical properties of heat-treated Mongolian pine lumber treated in atmospheric steam and pressurized steam, respectively. The results showed that dynamic fracture toughness, compressive strength parallel to grain, modulus of elasticity, and modulus of rupture of samples treated in both treatments were not statistically different. Samples treated in pressurized steam showed significantly reduced hygroscopicity and improved dimensional stability compared to those treated in atmospheric steam, indicating the potential value of heat treatment in pressurized steam.ZusammenfassungIn einer orientierenden Studie wurden die physikalischen und mechanischen Eigenschaften von Schnittholz aus mongolischer Kiefer untersucht, das unter normaler Dampfatmosphäre oder unter Dampfdruck Wärme behandelt wurde. Die Ergebnisse zeigten, dass sich die Schlagbiegefestigkeit, die Druckfestigkeit in Faserrichtung, der E-Modul und die Biegefestigkeit der Prüfkörper bei beiden Behandlungen nicht signifikant unterschieden. Verglichen mit den unter atmosphärischem Dampf behandelten Proben zeigten die unter Druckdampf behandelten Proben eine signifikant reduzierte Hygroskopizität und eine verbesserte Dimensionsstabilität. Dies weist auf den möglichen Nutzen einer Wärmebehandlung unter Dampfdruck hin.

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