METHOD OF PRODUCTION OF COMPOSITE MATERIAL FROM ALUMINUM ALLOYS (VERSIONS) AND COMPOSITE MATERIAL MADE ACCORDING TO THIS METHOD Russian patent published in 2003 - IPC

FIELD: powder metallurgy; technology of production of heat-resistant and wear-resistant composite materials on base of aluminum by mechanical alloying; manufacture of pistons for internal combustion engines. SUBSTANCE: according to first version, proposed method includes high-energy mechanical treatment of starting ground material in inert atmosphere for forming activate mixture and hot molding of this mixture for obtaining required material; used as starting raw material is mixture containing 10- 25 vol.% of aluminum oxide and the remainder being preliminarily ground aluminum chips; high-energy treatment of said mixture is effected for 15-120 minutes; hot molding is performed at temperature not exceeding the temperature of beginning of recrystallization of aluminum alloy; prior to hot molding, cold two-sided molding is performed for obtaining density of material of no less than 80% of relative density. Preliminarily ground chips of alloy are obtained by grinding chips no more than 5 mm in size in planetary activator; powder at dispersivity of 8-12 mkm is used as aluminum oxide powder. According to second version, activated mixture is obtained through internal oxidation of alloy in the course of high-energy treatment in planetary activator. Material thus obtained is characterized by long-term hardness HB3501

no less than 16 kgf/sq mm and temperature coefficient of linear expansion between temperatures of 20 to 400 C not exceeding 20*10^-6K^-1. Proposed method ensures production of material possessing isotropy of properties , high density at improved mechanical and physical properties and stable mechanical properties in the course of time. EFFECT: enhanced efficiency; improved mechanical and physical properties. 17 cl, 4 dwg, 3 tbl, 2 ex