Physical properties and termite durability of maritime pine Pinus pinaster Ait., heat-treated under vacuum pressure

Abstract

An original heat treatment performed under vacuum pressure was investigated. Maritime pine samples were treated at six different temperatures: 140, 160, 180, 200, 230 and 260°C. The physical and mechanical consequences, i.e. bending strength (MOR), modulus of elasticity (MOE), hygroscopic behaviour, equilibrium moisture contents and anti-swelling efficiency (ASE) were studied. A no-choice feeding test according to the NF EN 117 standard was achieved. Temperatures up to 200°C had no significant effect on wood properties. However, at 230 and 260°C, the decrease in MOR was severe, reaching 42.5 and 62.5%, respectively. Whatever the treatment conditions, wood samples were still highly degraded by termites, revealing no increase in their durability.