Energy Coupling Model And Tooth Surface Topography Of Femtosecond Laser Machining Of Face Gears

Face gears play a decisive role in mechanical space staggered transmission.The transmission power process has the advantages of large coincidence,can withstand large loads,and stable high-speed operation.It is widely used in large-scale equipment machinery,aerospace fields,etc.The tooth profile of the face gear is complex,the technical requirements are high,and the manufacturing is difficult.At present,the foreign face gear production technology and equipment are in a closed state,and the precision machining accuracy of the domestic face gear is about two levels lower than that of foreign countries.In order to overcome these technical problems,this paper adopts femtosecond laser trimming technology to realize micro-nano machining of face gear materials.The femtosecond laser cutting process realizes the precise cutting of tiny parts and is extremely flexible.With appropriate process parameters,precise cutting of parts with complex structures can be achieved.In this paper,the basic theory,model simulation and machining experiments are combined,and the research on the energy coupling model of femtosecond laser finishing tooth surface ablation and tooth surface morphology is carried out.The core content of the research is as follows:The difference between single-pulse and multi-pulse ablation of face gear materials is studied.By adjusting the energy density and power of the femtosecond laser,the critical point of ablation of the face gear material 18Cr2Ni4 WA was obtained.Comparing single-pulse laser and multi-pulse laser ablation of tooth surface pits,it was concluded that the cumulative effect of multi-pulse energy would make The material on the surface of the pit undergoes secondary ablation,thereby forming a small convex structure on the surface of the pit,which affects and hinders the ablation effect of the subsequent material.Research on material-to-material effects and modeling simulation of femtosecond laser ablation of face gears.In this paper,the component mutual temperature induction effect in the dynamic effect of the face gear material and the energy accumulation effect of the multi-pulse ablation material are considered.The mutual temperature induction effect of material composition is based on the non-Fourier heat transfer phenomenon and the two-temperature equation during femtosecond laser ablation of the face gear material,and the energy heat transfer model of the femtosecond laser ablation of the face gear material is established.By studying the multi-pulse energy accumulation effect,the critical energy density value of the femtosecond laser for multi-pulse ablation of the face gear is obtained.By coupling the compositional mutual temperature induction effect and the multi-pulse energy accumulation effect when ablating the face gear material with the two-temperature equation,the energy-coupled heat transfer model of the femtosecond laser ablation of the face gear is obtained.The two heat transfer models were simulated with COMSOL software respectively,and the temperature field variation law of femtosecond laser ablation of surface gears with different energy densities was obtained,and the parameter range of ablated tooth surface materials was obtained.Experimental study on tooth surface topography of femtosecond laser ablation of face gear materials.The experiment of femtosecond laser ablation of the face gear material is carried out,and the ablation experiment of the face gear is carried out in combination with the simulated parameter range.Detect the diameter and depth of the ablation pit;detect the depth,width and roughness of the ablation line;detect the depth and roughness of the ablation surface.The influence of different laser energy densities and pulse numbers on the size of the ablation pits and the depth and roughness of the ablation surface was analyzed.Through experiments,the relationship between laser energy density and power on the ablation line depth and roughness was analyzed.The results show that with the decrease of laser energy density and power,the quality of femtosecond laser processing is obviously improved,and the roughness is obviously optimized.In addition,there is no obvious melt residue in the ablation pits,lines and surfaces,and the ablation morphology is flat and basically has no heat affected area.According to the law of influence on tooth surface topography,the optimal parameter range of femtosecond laser finishing tooth surface is obtained.