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The porous metal material is composed of a metal and stomatal new composite material , a collection of metal properties (such as thermal conductivity , electrical conductivity , strength and toughness , etc. ) , and pore structure characteristics ( such as penetration , sound-absorbing , electromagnetic shielding, etc. ) , can be widely applied in transportation, aerospace , environmental protection , new energy , mechanical and chemical , electronic electrician , construction engineering field . A through-hole structure of the porous metal material have been widely used in the filtration and separation of the solids, liquids and gases . This paper presents a new method for preparation of a microporous aluminum foam for sintered the microporous aluminum foam mechanical properties of poor , that vacuum - pressure sintering - dissolution method , in order to obtain better mechanical properties of microporous aluminum foam . Al powder and NaCl as raw material , through mixing , molding , preparation of microcellular foam aluminum vacuum - pressure sintering and dissolved four processes . Add 2% Mg powder particle size and content of the pore-forming agent , compacting pressure , sintering temperature , sintering time , sintering pressure on the pore structure , microstructure and properties of . The main findings are as follows : ( 1) vacuum - pressure sintering - dissolved prepared by a porosity of 44 to 61% , an average pore size of 55 ~ 230gm, uniform pore structure of microporous aluminum foam . With the pore-forming agent content and particle size increases, the increase of the porosity and the average pore size of the microporous aluminum foam . (2) a porosity of 55%, under the conditions of an average pore diameter of 110μm , the flexural strength index, to obtain the optimum parameters for the preparation of microcellular foam aluminum : pressing pressure 500MPa , a sintering temperature of 650 ° C , the sintering time was 2h , sintered pressure 150 to 200 MPa , the Mg content of 2 % , the flexural strength of the material prepared under this condition was 44.7MPa . (3) Microstructure studies show that with the sintering temperature , sintering time was prolonged , the sintering pressure is increased , and 2 % of Mg added , microstructure improved significantly . ( 4) the flexural strength of the pore structure of microporous aluminum foam has an important impact , with the increase of the porosity and the average pore diameter , the microporous aluminum foam flexural strength gradually decline . (5) a porosity of 55%, average pore diameter of 110μm , the microcellular foam of aluminum relative permeability coefficient was 71.3 m3 · h-1 · m-2 · KPa-1, having good penetration properties . The paper provides a new method for preparing high strength aluminum microcellular foam , microcellular foam aluminum filter material development .
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