| The purpose of this project is to prepare a lightweight,high strength,high ductility material of the composite,the study of ultrafine grain ARB also has important significance.Because the multilayer of cold rolled sample has the disadvantage of low plasticity,aiming at this problem,this paper designs the pack rolling and annealing process,Successfully preparing the different structure of 3003/4343 and 3003/8011 aluminum alloy laminated composite plate,and carry out detailed research and analysis.This paper use the analysis method of metallographic microstructure,tensile fracture scanning,hardness test,tensile test and transmission electron microscopy for different structure of 3003/4343 and 3003/8011 aluminum alloy laminated composite plate,and adopt the way of low temperature annealing on mechanicalproperties and microstructure of the optimization.The composite laminates of 3003/4343 aluminum alloy and 3003/8011 aluminum alloy laminated plate with different layers were prepared by cold rolling method.The effects of microstructure and mechanical properties of different layers of aluminum alloy laminated plates when cold rolled and annealed were systematically investigated and analyzed.The main conclusions are as follows:(1)Successfully prepared 3003/4343 aluminum alloy laminated plate.With the increase of the number of composite layers(from 12 to 96 layers),the composite mechanical properties of the composite plate have been significantly improved1)cold rolled:With the increase of the number of composite layers,the tensile strength of the composite plates increased from 130.3MPa to 213.8MPa,and the yield strength increased from 126.3MPa to 184.7MPa,under the same elongation ratio.The yield ratio decreased from 0.967 to 0.864.Erichsen increased from 5.97 to 6.43.2)annealed at 200?×30min:With the increase of composite layers,the tensile strength increased from 159.8MPa to 253.OMPa,and the yield strength increased from 158.4MPa to 216.1MPa,and the elongation rate increased from 2.7%to 4.5%,and the yield ratio decreased from 0.990 to 0.854.Erichsen decreased from 8.33 to 7.36.3)annealed at 300?×30min:With the increase of composite layer,the tensile strength increased from 156.9MPa to 198.9MPa;the yield strength increased from 144.5MPa to 161.8MPa;the elongation rate increased from 3.2%to 5.9%;the yield ratio decreased from 0.921 to 0.813.(2)With the increase of the number of composite layers(from 12 layers to 96 layers),the micro structure of the multilayered structure of the composite plate is improved.The microstructural observation shows that the microstructures of the 96 layers composite plate after annealed at 300? are completely recrystallized to form finer equiaxed grains.The organization is more uniform,the layer spacing decreases from 97.14 ?m of 12 layer to 28.57 ?m of 96 layer.With the increase of the number of layers,the tearing ridge density increases and the dimple increases.From the fracture morphology of the cup specimen,with the increase of the number of layers,the way of punching fracture is changed from inhomogeneous deformation to uniform deformation.(3)Compared with 3003/4343 aluminum alloy laminated composite plate,the mechanical properties of 3003/8011 aluminum alloy laminated composite plate are better.The tensile strength of 3003/8011 aluminum alloy laminated composite plate 12 layer after annealing at 300 C was 197.5MPa,and the yield strength was 165.7MPa,and the elongation was 5.1%,and the Er was 9.0.The difference of performance between them is related to their layered composite structure... |
PDF Full Text Request