Determination of effects of boron compounds on some physcial mechanical and biological properties of wood

In this study, Calabrian pine (Pinus Brutia Ten.) and beech wood (Fagus Orientalis Lipsky.) samples were impregnated according to ASTM 1413 standards with six different solution concentrations of boron compounds and it was aimed to investigate the resistance changes on some mechanical, physical properties and biological of these samples. For this purpose, samples were left in borax (BX) boric acid (BA) and sodium per borate (SP) impregnations and 1% 2% 3% 4% 5% and 6% solution concentrations for 60 minutes equivalent to 760 mm Hg¯¹ 30 minutes of prevacuum and 30 minutes of free diffusion. Some of the samples were varnished with also polyurethane, synthetic and waterbased varnishes. Prepared samples were tested against, retention amount, retention rate, density, higroscopicity value, bending resistance, elasticity module, pressure resistance, fire resistance, and dry film thickness, gloss value, pendulum hardness value, surface adhesiveness resistance of varnishes resistance to white decay fungus according to ASTM or TS EN standards. Test results show that as the solution concentration amount increases, density, retention rate and amount, higroscopicity value and fire resistance values of both samples also increases and bending resistance, elasticity module and pressure resistance values are decreases on average 20%-40% ratio. All solution concentrations showed resistance to white decay fungus. On impregnated and varnished samples, highest dry film thickness observed on synthetic based varnish, highest pendulous hardness value observed on 6% BX solution, highest surface adhesiveness resistance observed on beech wood samples processed with 1% BX solution. As a results, as the solution concentrations of boron compounds increases, some decrease observed on mechanical properties and increase observed on physical properties. According to the results it is suggested that low concentration solutions (2%-3%) are appropriate where wood will be under mechanical resistance and high concentration solutions are appropriate where wood will be under physical effects.