Anisotropic electrical conductivity of green timber within $$20-90^{\circ }\hbox {C}$$ temperature range

Abstract

Electrical conductivity (EC) of the unseasoned timber of three softwood species (Pinus radiata, Pseudotsuga menziesii, and Sequoia sempervirens) and one hardwood species (Eucalyptus globoidea) was studied over the temperature range of $$20-90^\circ \hbox {C}$$ . EC was measured in sapwood, transitional wood, and heartwood in the three principle grain directions. All species exhibited similar behaviour: (1) heartwood EC was lower than that of sapwood and (2) EC increased with temperature. P. radiata samples from two regions of New Zealand’s South Island showed variation of EC by a factor of two in the longitudinal direction; however, in the radial and tangential directions, the EC variation was less pronounced. This work seeks to provide possible explanations for EC variation in green wood and to propose suggestions for future research.