Study On Preparation Technology Of Melt Semi - Continuous Foaming Of Aluminum Foam

Aluminum foam is a kind of integrating structural and functionality composite material. It has widely application prospect in automobile, aviation, biological and other areas. But the large scale of industrial production of aluminum foam and application in the world has not been achieved for its high cost of production. Preparation of the pore structure to achieve uniform method of continuous aluminum foam is an effective way to solve this problem.Aluminum foams produced by melt forming method. The preparation of semi continuous aluminum foam was studied by the equipment of adding foaming agent continuously which was made by myself, raw material is ZL111 alloy. The uniform pore structure aluminum foam (average pore size is 3-5mm, porosity is 70-87%) were obtained. The compression properties of foam aluminum with different porosity were studied The main results were listed as follows:(1) The equipment of adding and dispersing of foaming agent was designed and fabricated.(2) The homogeneous dispersion of foaming agent was achieved through the research on dispersion of foaming agent using the above mentioned equipment. The optimized process parameters:melt flow velocity is 6.11g/s, stirring blade tilt angle is 30 degrees, dispersing temperature of TiH2 is 610℃, stirring speed is 3000r/min.(3) The uniform pore structure of ZL111 aluminum foam (average pore size is 3-5mm, porosity is 70-87%) were obtained through the experiment of semi continuous foaming preparation of ZL111. The optimized process parameters of ZL111 alloy foaming preparation were listed as follows:the temperature of fusion and heat preservation is 610℃; the content of Ca is 1.5wt%; the time of stir and heat preservation is 12 min; the frequency of foaming agent transport is 9Hz; the time of foaming agent dispersing is 60s; the temperature of foaming heat preservation is 605℃; The foaming time is 330s.(3) Though the experiment of foaming preparation of ZL111, the ZL111 alloy foaming with uniform pore structure was successfully prepared, the obtained alloy foaming has the average diameter of pore 3-5mm, the porosity is about 70-87%. The optimal processing parameters of preparation of ZL111 alloy foaming were listed as follow:the temperature of fusion and heat preservation is 610℃; the content of Ca is 1.5wt%; the time of stir and heat preservation is 12 min; the frequency of foaming agent transport is 9Hz; the time of foaming agent dispersing is 60s; the temperature of foaming heat preservation is 605℃; the foaming time is 330s.(4) Along with the increasing of porosity, ZL111 alloy foam densification strain is ascend, the yield strength and energy absorption are decreased. The porosity, Yield strength and energy absorption of ZL111 alloy foam is up to 85%,12.1MPa,5.351 MJ/m3 respectively.Aluminum foam is a kind of integrating sructual and functionality material. It has widely application prospect in automobile, aviation, bio-logical and other areas. But the large scale of industrial production of aluminum foam and application in the world has not been achieved for its high cost of production. Preparation of the pore structure to achieve uniform method of continuous aluminum foam is an effective way to solve this problem.