Experimental study on machinability of bamboo scrimber in abrasive belt sanding assisted by CO₂ laser ablation
摘要
As an engineered bamboo product, bamboo scrimber has gained increasing attention. The high density and composite structure make it difficult in mechanical processing. In this study, a method of CO2 laser-assisted sanding (LAS) was applied to investigate the machinability compared with conventional sanding, which was achieved through analyzing laser ablation, sanding power, sanding temperature, surface morphology and profile. V-shaped grooves were generated by the laser ablation, while numerous cavities and charred areas were observed, indicating significant influence on the anatomical structures of bamboo scrimber. Higher specific sanding power and temperature were measured during LAS. This could be attributed to more friction and fluctuation caused by the laser-ablated grooves with 0.5 mm spacing. The laser-induced carbonized layer can be removed by following mechanical sanding. The surface integrity after LAS was composed of ploughed ridges, fiber fractures and hierarchical debonding. It can be inferred that laser pretreatment promotes brittle fracture and interfacial failure, thereby affecting material removal efficiency. LAS produced less upheaval and burrs according to the results of ultimate surface roughness at deeper cutting depth, which showed promise for enhancing bamboo scrimber surface finish despite of the elevated power consumption. This study provided some useful insights into understanding the complex interactions between laser treatment and subsequent mechanical sanding of bamboo scrimber.