Microcellular Foam Aluminum Preparation Of Basic Research

Metal foam is a composite material consisting of metallic matrix and gas bubbles. Metal foam not only has metal properties such as heat conductivity, electrical conductivity, high strength and toughness, but also has properties of cell structure as filtration, sound absorption and electromagnetic shielding. It is widely used in automotive and transportation, aerospace, environment protect, new power, mechanical chemistry, electronics and construction. Open cell metal foam has being widely used in these fields such as filtrating and separating solid,liquid and gas.To solve the problem of lower mechanical property, a new process of fabricating micro-pore aluminium foam has been provided in this paper. The micro-pore aluminium foams by vacuum-pressure sintering-dissolution process would have higher mechanical properties.The micro-pore aluminium foams have been fabricated by the vacuum-pressure sintering-dissolution process which is by means of mixing, compacting, sintering and dissolution Al and NaCl powders. The influences of factors include NaCl size and content, compacting pressure, sintering temperature, sintering time and sintering pressure on cell structure, micro-structure and properties were researched at the condition of Mg content 2%. The results as follows:(1) Based on the vacuum-pressure sintering-dissolution process micro-pore aluminium foams with the porosity 44-61%, the average pore size 55-230μm, and uniform cell structure have been fabricated. The porosity and average pore size of micro-pore aluminium foams will increase with increases in NaCl size and content.(2) The optimized parameters of fabricating micro-pore aluminum foams with porosity 55% and average pore size 110μm have been got:compacting pressure of 500MPa, sintering temperature of 650℃, sintering time of 2h, sintering pressure of 150-200 MPa, Mg content of 2%. In this condition, the bending strength of micro-pore aluminium foam is 44.7MPa.(3) The micro-structure was improved obviously with increasing of sintering temperature, sintering time, sintering pressure and content 2% Mg.(4) The cell structure has important effect on bending strength. The bending strength decreases with the increasing of porosity and average pore size.(5) The relativity permeability coefficient of micro-pore aluminium foams with porosity 55% and average pore size 110μm is 71.3 m3·h-1·m-2·KPa-1. So it can be used in filtration and separation fields.This paper describes a novel vacuum-pressure sintering dissolution process for fabricating micro-pore aluminium foams. It is meaningful to promote the development of micro-pore aluminum foams filtration materials.