| In recent years, with the rapid development of computer technology and the maturity of finite element numerical simulation method, the numerical simulation technology is widely used in material science field. Using this method, we can predict the manufacturing process and mechanical property of composite material, which provides evidence for improving manufacturing technique and combining ideal composite material. This research is mainly focused on bi-metal laminated composite. This kind of material is promising in auto, aerospace and national defense industry with its superior mechanical, shock absorption and anti-fatigue properties, and it is widely emphasized all over the world. This kind of material is made of two or more than two metal materials with different physical, chemical and mechanical property on the interface. In that way, we can both maintain the original characteristics of material in each layer and make the physical, chemical and mechanical properties more superior than a single material at the same time. Thus the comprehensive performance of material is improved. it also provides better condition to properly material choosing and reducing the cost of manufacturing products.Firstly, the thesis gives a detailed introduction on the manufacturing and application of bi-metal laminated composite, trying to give readers an overall knowledge of this material. Then, by using finite software into the simulation of material mechanical property, it makes numerical simulation to the mechanical property of Al/Fe laminated composite (including tensile, bending and shock mechanical property). Here are the conclusions:1. By using finite element software MSC. Patran,MSC. Nastran,ABAQUS , numerical simulation can be made on the Al / Fe laminated composite material of the mechanical properties (stretching, bending, impact properties). Compared with the experimental methods, the simulation is faster, more convenient, more timesaving and more materials saving and more credible. Performance evaluation and structural design of the material can be based on this.2. Making tensile numerical simulation on the Al / Fe laminated composite material. when the load PX =1000N and material geometry size=100mm×20mm×(2+2) mm,too, Al sideσmax =53.5 MPa , Fe sideσmax=93.3 MPa .3. Making bending numerical simulation on the Al / Fe laminated composite material. When PZ = -1000N, material geometry size=500mm×100mm×10mm; in linear elastoplastic,maximum stress of pure iron and pure aluminum is 294 MPa ; the largest displacement values is respectively 25.0 mm, 79.4mm. When Al / Fe laminated composite material, in linear elastoplastic,the maximum stressσ=280 MPa ,the maximum displacement value is 47.7 mm.4. Making impact numerical simulation on Al / Fe laminated composite material. when the geometric size of materials=100mm×100mm×(5+5) mm, imposed v Z=400m/s in the middle node, node 5731σmax=2.5 MPa ; node 2666σmax=1.6 MPa ;node 1735σmax=3.7 MPa ; maximum displacement value of the three nodes is 0.0038mm; maximum stress of edges of the nodes 5721,2666,1735 ,t = 0.005s should be 0.245 MPa,0.225 MPa,0.735 MPa .5. As the thermal expansion coefficient of the two kinds of material which composite the bi-layer metal composite material is different, in the presence of temperature difference conditions, the composite material will have a structural thermal stress. Using the thermal stress analysis of finite element analysis software to make the heat stress analysis on the dual-layer metal laminated composite material, it is concluded that when surface temperature of the outer side of aluminum is -30℃, surface temperature of the outer side of iron is 270℃, maximum heat stress of bi-layer metal laminated composite material is 111 MPa , middle regional heat stress is 98.6MPa , the maximum displacement value is 0.909 mm. Using thermal stress easing and functional gradient materials ( FGM ) to optimize the structure design of the aluminum / iron laminated composite materials and analyzed of the distribution of index, gradient thickness, the transitional floors and heat stress. When the components of that index, gradient thickness, the transitional floors respectively is p = 1.0, h = 5.0mm, n = 4, the heat stress and displacement value of composite material structure reach their minimum value.
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