Effect of boron impregnation on the density and dynamic modulus of three angiosperm woods

Introduction: Wood is a biodegradable material and its use requires information on the effect of protective substances on its mechanical properties. In such a way that it is important to develop technology for its conservation when it is in service.Objective: To impregnate with boron salts using the hot-cold bath process test specimens of Fraxinus americana, Albizia plurijuga and Spathodea campanulata. Method: Boron salt retention, density, wave velocity and dynamic modulus of the wood were determined. Stress wave tests were performed before and after the impregnation treatment.Results: The retention increases as the concentration increases and decreases as the density of the wood increases. No statistically significant differences were observed between the density and wave velocity samples of each species. No differences were found for the elasticity modules of S. campanulata. For F. americana and A. plurijuga differences were identified.Conclusions: The results suggest that the retention capacity of boron salts from wood depends mainly on the species. The average values of boron salt retention for concentrations of three percent were greater than the lower toxic retention limit to meet the minimum requirements of the standards for wood used indoors. For engineering design and calculation purposes, it is advisable to consider the scope of the results of this research that is limited to small-sized specimens.