Study On Strengthening And Properties Of Open-cell Aluminum Foams

Because of owning low density、high specific strength、good compression、good energy and sound absorption capacity 、 damping property 、 electromagnetic interference shielding and many other excellent properties, open-cell aluminum foams can be applied in automobile、machinery、aerospace、petrochemical industry、transportation、military industry and many other industries as both structural materials and functional materials. So, as a new kind of material, open-cell aluminum foams have a wide application prospect and high value in use. However, with the development of economic construction, people put forward higher performance requirements to open-cell aluminum foams, and also hope that aluminum foams can be used in more rigorous environments. So, it is a new task and new direction to improve the performance and application scope of the open-cell aluminum foams.In this paper, we prepared open-cell aluminum foams through infiltration casting process at first, strengthened the open-cell aluminum foams through alloying and surface treatment technologies individually, and then studied the properties of aluminum foams in room temperature, high temperature and corrosion environments. In addition, the sound absorption properties of the open cell aluminum foams were also studied.The research results show:1. With the application of spherical calcium chloride as the material for making the preform, through infiltration casting process we prepared the spherical open-cell aluminum foams with uniform pore distribution, good connectivity and controllable structure. By Micro-Arc Oxidation and electroless plating technology, we prepared uniformly distributed micro-arc oxidation ceramic coatings and electroless deposited Ni-P alloy coatings on the surface of aluminum foams;2. Open-cell pure aluminum foams have good compression performance and energy absorption capacity and energy absorption efficiency. The main factor that affect the compressive strength and energy absorption properties of the aluminum foam is the porosity of the aluminum foams, and the influence of the pore size is very small;3. The compressive strength and energy absorption capacity and energy absorption efficiency of open-cell Al-Si foams are improved compared with that of pure aluminum foams.,and the properties of f Al-Si foams with eutectic composition increase most. While hypoeutectic Al-Si foams 、 aluminum foams containing trace silicon and hypereutectic Al-Si foams decrease in turn. The hypereutectic Al-Si foams aluminum silicon show obvious brittle behavior, and the properties of hypereutectic Al-Si foams can be improved to a certain extent through modification treatment;4. The compression strength and energy absorption capacity and energy absorption efficiency of open-cell aluminum foams can be increased obviously by MAO treatment and electroless plating treatment, so we know that surface treatment strengthened the compression performance of aluminum foams effectively. The compression fracture mode of aluminum foams with MAO and electroless plating is interface debonding;5. The compressive properties and energy absorption properties of the open-cell aluminum foams under corrosive and high temperature environment all attenuate. MAO and electroless plating treatment of aluminum foams can reduce performance degradation in corrosive and high temperature environment performance obviously, enhance the compression performance of aluminum foams in corrosive and high temperature environment;6. Spherical open-cell aluminum foams have good sound absorption performance. With the decrease of pore size and porosity, the sound absorption coefficient of the aluminum foams is improved, and the sound absorption ability is enhanced. MAO treatment and the setting of back cavity can improve the sound absorption coefficient of the aluminum foams to a certain extent.