Study On Machining And Clear Painting Properties For Three Eucalyptus Plantation Species

Completely testing for machining and painting properties of Eucalyptus urophyllax E. grandis, E. exserta and E. citriodora plantation wood has been carried out, which will provide theoretic base and some useful technical information. Juglans cathayensis, the materials commonly used for domestic solid wood furniture production is as comparative specimen.Machining properties testing was mainly based on ASTM D1666-87 standards and also combined internal practical situation. Six items, which are planning sanding shaping boring mortising turning, have been fully studied. The machining defects have been identified and distinguished. Stereotype microscope and SEM were used for observing these defects which in order to reveal its essential destroying form. The study shows:(1)During single item test, Planning Shaping and Mortising ability of three Eucalyptus species are better than Juglans cathayensis. For boring ability (The holes manufactured by brad-point bit.) three Eucalyptus species and Juglans cathayensis stand a same grade. As planning ability three Eucalyptus species is low one grade than Juglans cathayensis, however three Eucalyptus species planning defect type is simpler and magnitude is less.(2)For general assessing of machining ability, three Eucalyptus species obtain high marks than Juglans cathayensis(E. urophyllax E. grandis, 41 points; E. exserta, 40 Points; E. citriodora, 37 points; Juglans cathayensis, 28 points. The general point is 50.), which reveal three Eucalyptus species have a good machining properties.From the viewpoint of vision circumstance and aesthetics, clear painting property for three species of Eucalyptus plantation wood has been researched completely. Nitrocellulose varnish Alkyd varnish and Polyurethane varnish, which are commonly used for wood products painting, were used for the study. The parameters of chromatic aberration and gloss have been measured and then analyzed. Some suggestions are given. Thy study reveals:(1)The change of chroma parameters is obvious in species. The variation scale For E. citriodora painted by three varnishes is less than E. urophylla E. grandis E. exserta and Juglans cathayensis (Except the parameter /dhab painted by Alkyd Varnish). The latter variation scale is closer.(2)For numerical value of chroma parameters change after painting, Alkyd Varnish and Polyurethane Varnish are closer and more higher than Nitrocellulose Varnish.(3) For gloss increasing ,Alkyd and Polyurethane Varnish are faster than Nitrocellulose Varnish. To decreasing and improving anisotropies of gloss, Alkyd and Polyurethane Varnish are also better than Nitrocellulose Varnish.