Selected Malaysian Wood CO2-Laser Cutting Parameters And Cut Quality

Abstract

Laser has been used to cut most non-metallic materials very efficiently and successfully because these materials are highly absorptive by the CO2 laser wavelength of 10.6 10.6µm. Laser cutting process has been found to be reliable in loads of applications, with several advantages over other mechanical means in producing successful cut of even thermally sensitive materials such as wood. Various works which have been conducted to resolve the interaction between laser and wood but an ultimate guideline to produce the best cutting results are still undecided. This latest experiment was performed on Malaysian light hardwood namely, Nyatoh (Palaquium spp.), Kembang Semangkok (Scaphium spp.), Meranti (Shorea spp.) and normal Plywood using low power carbon dioxide laser machine with 500 Watt maximum output. The low power laser machine (Zech Laser model ZL 1010), equipped with a slow flow CO2 laser producing maximum output power of 500 watt on beam mode of TEM01 is employed. The processing variables taken into investigation were laser power, nozzlestandoff distance (SOD) or focal point position, nozzle size, assist gas pressure, types of assist gas, cutting speed and delay time. The wood properties observed were thickness, density and moisture content of the wood. The analyses considered were of the geometric and dimensional accuracy (straight sideline length, diameter of circle, kerf width, and percent over cut), material removal rate, and severity of burns of the matters upon machining with compressed air or any assist gases. The relationship between processing parameters and types of wood with different properties were outlined in terms of optimum cutting conditions, the minimum burnt-effect achievable and the best cut quality obtained with minimal surface deterioration and acceptable in accuracy. From this present study a guideline for cutting a wide range of Malaysian wood has been outlined.