CO2 Laser Cutting of Particleboard, HDF and MDF

The purpose of this thesis is to reveal how the laser cutting parameters influence lasercutting of particleboard, HDF and MDF. The literature review introduces the basic principle of CO2 laser, CO2 laser equipment and its usage in cutting of wood-based materials. The experimental part focuses on the discussion and analysis ofthe test data and attempts to draw conclusions on the influence of various parameters, including laser power, focal length of the lens and cutting gas, on the cutting speed and kerf quality. The tested materials include various thicknesses of particleboard, HDF and MDF samples. A TRUMPF TLF2700 HQ laser equipment was used for the experiments. To obtain valid data, the test samples must be completely cut through without any bonding of wood fibre. The maximum cutting speed is linear dependent on the laser power in thecondition that the other parameters are constant. For each thickness of a specific material type, there is a minimum laser power for cutting. Normally, the topand bottom kerf widths increase with the enhancement of laser power. There may be a critical laser power which can generate the minimum cross-sectional kerf width. Lens of larger focal length may achieve higher cutting speed. As the focal length becomes larger, the top kerf width tends to increase while the bottom andcross-sectional kerf widths to the opposite. Of all cutting gases, oxygen can help achieve higher cutting speed. The gas pressure of nitrogen does not seem to have strong influence on the cutting result. Generally, 2 bar air is more preferable for higher cutting speed. For particleboard and MDF samples of larger thickness than 12 mm, 2 bar argon can be used to reach remarkably higher cutting speed than the 5 bar. Generally, the 190.5 mm lens can produce smallest total kerf width. The kerf sides of thicker samples are darker than the thinner ones. The sample darkness tends to be lower as laser power increased. 63.5 mm lens seemed tocause more darkness than other lens. 5 bar cutting gases can produce less dark side kerfs than 2 bar ones. Oxygen normally causes darker kerfs than other gases. No distinct differences were found between nitrogen and argon.