Ultraviolet Nanosecond Laser For The Surface Ablation Mechanism Of Hardwood

Wood has a high degree of diversity and variability,so more and more attention has been paid to improving the comprehensive utilization rate of wood,improving the original performance of wood and expanding its application range.Laser cutting and surface treatment of wood materials is an advanced processing technology developed and derived from the field of metal material processing.Traditional machining has certain limitations.The laser heat treatment process of wood materials is a process in which optics,thermology and mechanics are coupled and influence each other.Laser wood processing has the advantages of high machining precision,reducing the waste of wood resources,achieving the processing of complex shapes,no tool loss,and changing the physical and chemical characteristics of the wood surface through fine parameter regulation.In this paper,based on the research achievements of laser wood processing at home and abroad,a set of nanosecond laser processing system with ultraviolet wavelength of 355 nm was built,and the surface of selected wood(ash,oak,southern pine,red sandalwood)was processed by dotting,lineation and sweeping.By adjusting the laser power and checking the performance and stability of the laser processing system,the influence of parameters on the wood processing quality such as cutting depth,slit width,and heat-affected area was investigated.By using this laser processing system,combined with SEM,1H-NMR,ATR-FTIR,organic element analysis,formula method and other characterization and detection experiments,it is proved qualitatively and quantitatively that ultraviolet nanosecond laser can ablate both lignin and cellulose in red sandalwood,and lignin plays a major role in the absorption of laser energy during the ablation process.