To adopt a greener approach, a novel thermal treatment for wood was proposed. Poplar wood surface was treated by CO₂ laser and the surface color changes were evaluated by CIELAB color space. The treated and untreated surface were scanned by Epson scanner to measure lightness difference (ΔL*), red-green index difference (Δa*) and yellow-blue index difference (Δb*), then the total color difference (ΔE*) was calculated. The laser energy load on wood surface caused characteristic changes in the chemical component, which were determined by means of Fourier infrared spectrometer (FTIR). Response surface methodology (RSM) was used for modelling and to establish a relationship between color changes and laser modification parameters. The results showed that the feed speed, sweep width and laser power had significant effects on color changes of wood surface. The ΔE* increased with the increasing of laser power, however it decreased with increasing of feed speed and sweep width, because of the amount of heat transferring decreased with the increasing of feed speed and sweep width. The results of FTIR revealed chemical structure in the wood components, which is one of the reasons to the color changes of the wood surfaces. The established quadratic mathematical model applied to describe the relationship between color changes and laser modification parameters had a good prediction. It will be useful for selecting appropriate modification parameters to achieve desired color changes.

为了采用更环保的方法，提出了一种新颖的木材热处理方法。杨木表面经CO ₂激光处理，表面颜色变化通过CIELAB色彩空间评估。用Epson扫描仪扫描处理过的和未处理过的表面，以测量亮度差（ΔL*），红绿色指数差（Δa*）和黄蓝色指数差（Δb*），然后测量总色差（ΔE*）进行了计算。木材表面的激光能量负载引起化学成分的特征变化，这是通过傅立叶红外光谱仪（FTIR）确定的。响应表面方法（RSM）用于建模并建立颜色变化与激光修改参数之间的关系。结果表明，进给速度，扫描宽度和激光功率对木材表面的颜色变化具有显着影响。该ΔE*随激光功率的增加而增加，但随着进给速度和扫掠宽度的增加而减小，这是因为传热量随进给速度和扫掠宽度的增加而减少。FTIR的结果揭示了木材成分的化学结构，这是木材表面颜色变化的原因之一。建立的二次数学模型用于描述颜色变化和激光修改参数之间的关系具有良好的预测。选择适当的修改参数以实现所需的颜色更改将很有用。