Research On Properties And Fabrication Technique Of Aluminum Foam With Press-Dissolution-Vacuum Sintering Progress

Aluminum Foam (AF) is a type of functional material. It has many excellent physical and mechanical properties such as noise elimination, shock absorption and filtration. Therefore it can be widely used in environment protection, mechanical and chemical industry etc. The researches on preparation craft and various properties of AF have become popular in research of AF at present. This paper introduces a new method named Press-Dissolution-Vacuum sintering (PDV) that produces AF, in which Al is the base body and NaCl is space holder. The key process of manufacturing AF was studied. The influences of experiment condition and processing parameters on manufacture and properties of AF were analyzed, and the optimal technical parameters were decided The influence of the porosity and pore structure on properties of AF were studied. The properties of AF sintering in vacuum and nitrogen was compared and by different process routine were compared. The effects of rare earth oxide on properties of AF and its acting mechanism were investigated primarily. The results show that open pore structure AF with 50%-75% porosity can be produced with PDV method, in which pore structure can be easily controlled. The optimal processing technical parameters are that pressing under of 250MPa-350MPa pressure, sintering at 540℃ for 2 hours. The transverse rupture and the compression strength of the AF decrease with the increase of porosity. The damping property of AF improves with the increase of the porosity and reduction of the pore radius. Sintering in vacuum has many advantages such as avoiding oxidation, evaporation gases, degreasing, deoxidizing and accelerating diffusion etc, so the microstructure and flexure property and compressive property of AF went better than that sintering in N2 protection atmosphere. The flexure and compressive properties of AF produced by Dissolution-Sintering process were better than that by Sintering-Dissolution process with same sintering technics. The transverse rupture strength, transverse rupture energy. The damping property and the compressive property of AF increased first and then decreased with the increase of Y₂O₃.The transverse rupture strength and the damping properties of AF were optimal when the content of Y₂O₃ is 0.8wt%, and the compressive property was optimal when the content of Y2O3 is 0.5wt%. The flexure property and compressive property went bad, but the damping property improved when CeO₂ was added.