The influence of heat treatment severity (resulting from temperature) on the colour and gloss distribution changes of mahogany wood, and the effects of wood density on the responses to heat treatment were evaluated. The wood timbers with different densities were treated at 150°C to 200°C with an interval of 10°C and duration of 4 hours for heat treatment schedules. The colour parameters (lightness L^*, red-green axis value a^*, yellow-blue axis value b^*) and gloss (parallel and perpendicular to the grain) values of heat-treated wood were determined. The distributions of colour and gloss were analyzed using a frequency counts method. Results show that heat treatment resulted in the distinct decrease in L^* and b^*, while almost no change in a^* for mahogany wood. The lower gloss values were obtained in the wood after heat treatment. The colour and gloss uniform on the exposed surface of the wood was improved due to heat treatment. Heat-treatment induced colour and gloss changes were more effective in the samples with lower density. The effects of density on the colour and gloss variability in the original wood were reduced by heat treatment, and this reduction was more distinct at high heat treatment temperature. The total gloss change was found to be highly correlated with the total colour change of heat-treated wood.

中文翻译：

---

密度对热处理引起的木材颜色和光泽变异性变化的影响

评估了热处理强度（由温度引起）对红木木材颜色和光泽分布变化的影响，以及木材密度对热处理响应的影响。不同密度的木材在 150°C 至 200°C 下以 10°C 的间隔和 4 小时的热处理计划进行处理。测定热处理木材的颜色参数（亮度L ^*，红-绿轴值a ^*，黄-蓝轴值b ^*）和光泽（平行和垂直于纹理）值。使用频率计数方法分析颜色和光泽的分布。结果表明热处理导致L的明显降低^*和b ^*，而桃花心木的a ^*几乎没有变化。热处理后木材的光泽度值较低。由于热处理，木材暴露表面的颜色和光泽均匀。热处理引起的颜色和光泽变化在密度较低的样品中更有效。热处理降低了密度对原始木材颜色和光泽变异性的影响，这种降低在高热处理温度下更为明显。发现总光泽变化与热处理木材的总颜色变化高度相关。