Research On Fine Laser Etching Technology For Surface Pattern Of Metal Cladding Parts

High-performance antennas for high-speed aircraft are widely utilized in deep space exploration and manned space flight.Serviced as crucial parts to transmit and receive electromagnetic waves,it is usually postulated that performance of the aforementioned antennas directly determine the precision and stability of position and navigation,remote sensing and controlling,electronic countermeasures for high-speed aircraft.As to better satisfy increasing demands of the overall performance for high-speed aircraft and adapt to the serve working conditions such as high load force and vibration,the high-performance antennas must meet the ultra-high electrical capability,mechanical strength,requirement of form and position at the same time.The preciously fabrication of the high-performance antennas is thus a paramount affair in industrial fields.As a non-conventional machining technology,the pulsed laser processing,which has the advantages of no tool wear,no processing stress,etc.has exerted a tremendous fascination in the preciously fabrication of the high-performance antennas.Whereas,the industrial plasticmetal heterogeneous contracture of high-performance antennas presents stark difference of thermal physical properties and the copper-plated layer is as extreme thin.Those features determine the arduous issue to control the ablation depth for pulsed laser processing and even directly induces the failure of antennas.Additionally,the strips of high-performance antennas are designed with partial drastic changes of geometrical features,together with high geometrical performance demands,which bring about the complicated accumulating law of laser energy on the parts surface while pulsed laser processing and the unclear correlation between laser processing process parameters and laser ablation profile,seriously affecting the antenna electrical performance.Therefore,in order to better meet the high-quality processing requirements of highperformance antennas for high-speed aircraft,research on fine laser etching technology is conducted for complex metal patterns on the surface of cladding parts.The detail research contents are as follows.(1)Research on laser energy accumulation law on the parts surface for complicated scanning path.Assessment method for difference of pulsed laser energy distribution on planar and curved surface target parts is constructed to analyze the feasibility of approximate modeling with planar surface for curved one in pulsed laser processing.Comprehensively considering the discrete distribution feature of pulsed laser spots and the non-continuous overlapping of pulsed laser energy on target parts surface in nanosecond pulsed laser processing,the ideal of continuous approximation for discrete pulsed laser energy is harbored in solution of dynamic energy distribution for pulsed laser processing.Based on the proposed dynamic energy distribution model,correlation law between pulsed laser distribution and processing parameters is fast revealed fix-pointedly and quantitatively.(2)Solution of ablation profile for nanosecond pulsed laser processing.Based on the proposed dynamic energy distribution model,the ablation depth is solved at different points within pulsed laser scanning range and the ablation profile prediction model is proposed thus for nanosecond pulsed laser processing.Based on the proposed model,the feasible region of processing parameters is established here,considering the restriction for both optic performance of pulsed laser generator and dynamic performance of machining tool.Accordingly,phased and full process prediction of the cross-section profile of micro-grooves by nanosecond pulsed laser processing is achieved here.(3)Fine laser etching strategy of pattern complex geometrical feature for nanosecond pulsed laser processing.The assessment method for ablation profile symmetry in established to deal with the influence that curvature feature of laser scanning path has on pulsed laser ablation profile symmetry.Thus,methods to generate the side-step of scanning path for pattern with large curvature radius feature and to optimize the scanning path for pattern with finer curvature radius feature based on Frenet frame equation and curvature circle discretion-approximation to solve the concerned scanning path optimization for scanning path with complex equation or expression.The fine laser etching technology for surface pattern on of metal cladding parts proposed in this article can effectively describe the law of laser energy accumulation and the evolution of laser ablation contours on the surface of parts,and provide reliable theoretical support for laser processing process parameter setting and scanning trajectory optimization.The quality of antenna processing and the improvement of high-speed aircraft service performance have important practical application significance.