粗皮桉木材热处理位置对吸热量及升温速度的影响

Effect of temperature and testing position to heat absorption and temperature increasing rate during Eucalyptus pellita wood heat treatment

对粗皮桉Eucalyptus pellita木材采用辐射加热的方式进行真空热处理，研究处理温度及不同测试位置，包括板厚、长度及宽度位置因素，对木材板内单位质量吸热量（Qm）及平均升温速度（VTmean）的影响，用方差分析判定影响真空热处理过程的主要参数，以最小显著差法（LSD）多重比较分析其影响程度。结果表明：影响Qm及Ⅳ‰的主要因素为热处理温度及板材厚度，端距、侧距的影响不大；随热处理温度升高、板材厚度的增加，Qm及VTmean增大，当板材厚度差在20 mm以上时，Qm及VTmean在0．05水平上差异显著，采用真空热处理时需考虑由厚度造成的传热不均问题。若以吸热量衡量热处理效果，在120-240℃的温度段处理，可满足较广泛的热处理效果差异需求。

Eucalyptus pellita wood was radiation heated under different temperatures in vacuum condition. Ef- fect of different temperatures and testing positions, contains different wood board depths, lengths, and widths, to heat absorption per unit mass （Qm） and average temperature increasing rate （VTmean） were studied. Influence degree to 0m and VTmeanof the parameters were judged by analysis of covariance, and the degree of influence were weighed by LSD multiple comparisons. The results showed that： main factors which effecting VTmean and Qm during vacuum heat treatment were heat treatment temperature and testing board thickness, influence of dis- tance from test point to board top and side was quite limited; VTmean and Qm went up as heat treatment tempera- ture increasing and thickness enhancing, effect of depth increased significantly different at 0.05 levels when the depth difference reached up to 20 mm. The phenomenon of uneven heat transfer should to be taken into ac- count when the thickness of the treating board was more than 40 ram. [Ch, 3 fig. 5 tab. 12 ref]