| With the advent of new technologies and new industries,the requirements for the mechanical properties of metallic materials are also more and more harsh.A single type of metal or alloy is often limited by the scarcity of resources or lack of overall performance,it is difficult to meet the requirements of the rapid development of society.In this case,the laminated composite material because of its simple crafts and excellent performances,attracted more and more scholars and business attention.Due to its good formability,corrosion resistance and light weight,Aluminum is used in stainless-steel/aluminum,titanium/aluminum and so on.The project achieved the purpose of improving mechanical properties of 3003 laminated structure by the research of the impact of interfaces on the microstructure and mechanical properties;and obtained different microstructure,achieved the control of strength and toughness of 3003/8011 heterogeneous A1 alloy laminated structure by designing the arrangement of laminated.Firstly successfully producted monolayer 3003 boaed,8 layers 3003 laminated structure,16 layers 3003 laminated structure with the method of ARB.Systemically studied the rule of the laminated structure between microstructure and properties,and explored the impact of annealing temperature on the strength and toughness of laminated structure.Then successfully prepared three different 3003/8011 laminated structure with ARB,and compared their difference at microstructure and properties,eventually we got the optimal arrangement of laminated.The main conclusions are as follows:(1)3003 layered structure can obviously improve the comprehensive mechanical properties,with the increase of layers,almost the same strength,elongation has greatly improved,the comprehensive mechanical properties has been a sharp rise.3000?×30min annealing,the yield strength of single 3003 plate is 156.67 MPa,elongation is 4.17%;the yield strength of 8 layered structure is 144.67 MPa,elongation is 7.79%;the yield strength of 16 layered structure is 149.67 MPa,elongation is 13.98%.(2)With the increase of annealing temperature,the influence of layer on the mechanical property presents the trend of first rising and then reduce until disappear.Before annealing,the elongation of 16 layers 3003 laminated structure is 153%to the 8 layers,is 169%to the single 3003 plate;300?×30 min annealing,the elongation of 16 layers 3003 laminated structure is 179%to the 8 layers,is 335%to the single 3003 plate;And 550?×30 min annealing,the elongation of single 3003 plate is 32.79%,the elongation of 8 layers is 34.06%,the elongation of 16 is 35.08%.(3)Fracture morphology of the single 3003 plate is a dimple pattern,fracture morphology of 16 layers 3003 laminated structure is different obviously,both sides of the interface respectively generate overall plastic deformation to the opposite direction,the integral sliding is the largest contribution to the plastic deformation,this is the important reason for the plasticity of 16 layers 3003 laminated structure far more than single 3003 plate.(4)Compare the properties of the three plans of heterogeneous metal laminated structures,the properties of soft hard alternate plan is the most excellent.300?×30 min annealing,soft hard alternate laminated structure has excellent mechanical properties,the tensile strength is 147 MPa,yield strength is 130 MPa,elongation is 20.44%.(5)Compared with 16 layers 3003 laminated structure,the properties of heterogeneous 3003/8011 soft hard alternate laminated structure increased slightly.300?×30 min annealing,the elongation of soft hard alternate laminated structure is 146%to 16 layers 3003 laminated structure.By TEM,the deformation of 3003 layer is small and the dislocation density is low,most deformation happened in 8011 layer,it have amounts of dislocation slip band.When the dialocation slip to the high plasticity 8011 layer,it's difficulty to product crack,and even crack were producted,when it reached high plasticity layer,energy is absorbed and crack unfavorable extension. |
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