Research On Spinning Process Of Spherical Head Of Cu-Al Composite Plates

Because of its excellent comprehensive performance,laminated composite has a broad application prospect in manufacturing,especially the different properties of its various layers,so that they have unique advantages in occasions with large differences in internal and external service environments,such as spherical head of pressure vessel.Owing to the small batch and different kinds,deep drawing has problems such as poor flexibility,complex procedures,and high mold costs.Metal spinning is a kind of technology used for forming hollow rotating parts,which has the advantages of flexible process and simple mold,so it is appropriate to the formation of spherical heads.However,the mechanical properties of each layer are different,and the forming process is quite different from the conventional spinning,and the plastic deformation mechanism is complicated,there is no literature that has conducted in-depth research on the spinning forming of composite plates.Therefore,it is necessary to conduct a systematic study on the spinning forming of composite plate heads.Combined with numerical simulation,experiment and material characterization,the spinning process of composite plates was studied,and an analytical model of flange wrinkling was built,and the effects of feed rate,blank thickness and material performance parameters on flange wrinkle was explored;the effects of process parameters on spinning process was discussed,and effecting mechanism was also revealed;and the changes of the microstructure and properties of the spun parts were obtained.The verification shows that the theoretical model of flange wrinkling in spinning of dual-metal plates based on the energy method is reliable,further studies have found that the critical spinning forming angle increases with the increase of the total thickness of composite plate or the material strengthening coefficient,and decreases with the increase of the feed rate or the hardening exponent of the material.The results show that if the feed rate increases,the forming accuracy of the part will be reduced;if it decreases,the wall thickness will be excessively thinned.And this conclusion is the same as that of the radius of roller.However,the forming quality of the spun part is not obviously affected by the roller oblique angle.It is found that the grain size of the spun part along the direction of the generatrix decreases,and shows a gradient variation in the direction of the thickness.The hardness and elastic modulus of the spun part increase,and along the direction of the curved generatrix,the hardness value increases gradually.