Study Of Preparation And Energy Absorption Properties Of Aeronautic Aluminum Alloy Foam

Aluminum foam has many excellent properties, it could insulate noise, reduce noise level and absorb energy as well for its unique structural features, as a new functional materials, aluminum foam has been widely used in fields of aviation, aerospace, electronics, energy, and some other scientific or technology industries; 2024 and 6061 aluminum alloy have low densities and high strengths, and they have a good ability for the resistance of corrosion, they could also be heated for strengthening, so they are widely used in fields of aviation, construction, automobile manufacturing and other fields. While the research for aluminum alloy foam is relatively not too much.This these uses method of powder metallurgy- space-holder to produce open cell foam, the experiment consists of weighing- cold pressing- dissolution- Dry –Sinter five steps. This thesis studied and determined the optimum parameters during the preparation: the cold pressure and sintering temperature; Having prepared the foam with pore size range in 0.8 ~ 2.0mm and the porosity of 50% to 70%, having prepared 2024 aluminum alloy foam and 6061 aluminum alloy foam; Having studied the influence of pore size and porosity of the foam for the properties of absorbing energy; Having done T6 heat treatment for aluminum foam alloy, and studied the effects of aging on the properties of aluminum foam. Having determined the optimal parameters of heat treatment for 6061 aluminum alloy foam.The results show that: the spherical carbamide were used as the space holder, this Space-holder method could be used to prepare the open-cell foam with porosity from 50% to 70%, the process is simple and it could control precisely the pore size and porosity of the foam, the optimal parameters for the preparation of open-cell foam: cold pressure 500 Mpa, holding time 4min, optimum sintering process for aluminum foam is sintering under 650 oC for 3h, optimum sintering process for 2024 aluminum alloy foam is sintering under 570 oC for 3h. optimal sintering process for 6061 aluminum alloy foam is sintering under 610 oC for 3h. When porosity is the same and the pore size is less than 2mm, the bigger the pore size is, the higher the yield strength of the foam will be; when pore size range in this interval, the yield strength of the foam increases when porosity decreases, and the platform of stresses will also decrease.T6 heat treatment could not enhance effectively the properties of 2024 aluminum alloy foam, because it will cause weak plasticity, the material will break or collapse easily during the compression test. The 6061 aluminum alloy foam could be strengthened by solution(510oC + 1h) and aging(190oC + 2h), the yield strength of the material reaches 19.08 Mpa, stress plateau reaches 17.30 Mpa, properties of energy absorption has been improved by 28.2%, so T6 heat treatment can enhance effectively the energy absorbing properties of 6061 Al alloy foam.