| The aluminum alloy cross-rib panels are widely used in the aerospace field because of the character of light weight,high strength,and good fatigue resistance.But the cross-rib structure restricts the forming of the panels.Traditional method of forming has the problems of long cycle,severe rebound,and ribs can be easily broken.In this paper.The laser-induced forming method was used to study the taper forming of fan-shaped aluminum alloy cross-ribs panels.Firstly,this paper established a laser heat-induced forming finite element modelby according to the thermal coupling theory.The simulation of single-channel scanning revealed the regularity of temperature field,displacement field and strain stress.The characteristics of fan-shaped cross-bar forming were analyzed.The correctness of the simulation results was verified by experiments,which laid the foundation for the study of the subsequent scanning strategy.In order to reduce the undesired deformation in single-channel scanning,this paper studied the scanning strategy of the tapered cross-section of the fan-shaped cross-ribs.To improve the consistency of the deformation of the scanning line,a variable power scanning strategy,multiple scanning strategies at both ends and a comprehensive scanning strategy were proposed.Various scanning strategies were used to improve the consistency of the deformation of scanning lines by simulation analysis and comparison.effect.To reduce the edge effect,the influence of the scanning speed,laser power and the number of scans on the edge effect was analyzed.A scanning strategy for suppressing the edge effect was obtained and verified by experiments.The finite element analysis was performed on the overall distortion of the plate during the formation of multiple scan lines,and a scan strategy for correcting warped plates was proposed and verified in experiments.Based on the conclusions above,this paper conducts a tapered surface forming test.According to the geometric characteristics of the cone surface,the bending angle and z-direction displacement of the forming are calculated,and the scanning path of the integral forming of the tapered surface is determined.The tapered surface forming test of 2×2 mesh fan-shaped cross ribs was carried out.The forming error was analyzed and the rationality of the overall scanning strategy of cone forming was verified.This scanning strategy was copied to the cone-shaped forming of the fan-shaped cross-ribbed panel with 6×7 grids,and the scanning parameters were modified.The high-precision tapered cross-ribbed panel was obtained. |
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