Technic Rsearch On Foam Aluminum By Coating AlPO₄/TiH₂

As a new functional and structural material, Foamed aluminum is widely used in aerospace, auto, and architecture industry , etc, owing to its lightweight, fire retardancy, amortization, high energy absorbing and other outstanding physical properties. Synthesis of foaming aluminum by Fused mass foaming method is attached more and more importance to large science and technology staff with the following advantages of its simple technics, possibility of producing massive foaming aluminum and its simple mannfacturing facility over other technics. The key technology of syiitliesiziiig foaming aluminum with fused mass foaming method is how to put off the releasing gas speed of TiH₂ in high temperature. So it is very meaningful to study on the TiH₂-coated treatment and the frothing behavior during the frothing process, which can result in the technical improvement on the synthesis of foamed aluminum, controlling the size of air bubble and getting foaming aluminum with high porosity.The key point of synthesizing foaming aluminum by fused mass froth method is to make the TiH₂ releasing gas release slowly. At present, to coat TiH₂ is widely used as a conventional method. Many methods are applied, generally classified into physical and chemical methods.In this experiment, TiH2-coated by self-made agglomerant AlPO₄ is synthesized, then coated-TiH₂ is put into fusing viscosity increaser aluminum liquid, stir, heat preservation froth. This experimentation makes coated TiH₂ by AlPO₄,. Orthogonal experiment is used to determine the proper parameters of the coating technology, microstructure of coated TiH₂ is evaluated by SEM; the hydrogen releasing property of coated TiH₂ powder is measured by releasing gas device.It can be concluded from those tests that the most influencing parameter to TiH₂ -covered is PH, and the following ordinal ones are temperature, time, stir speed.The releasing gas time of TiH₂ is only 60s in the experiment.The best coating condition is PH=8 and the proper parameters should be as follows: stir time with 300s, stir speed with 300r/min, temperature from 100℃ for synthesis of cover agent. The best weight ratio of coated -TiH₂ to aluminum is 0.7%.