Abstract

The aim of this work is to develop 7075 based grafen/graphite added metal matrix compostite for different applications. A series of aluminum based P/M MMC’s alloys were prepared with grafen and graphite addition to 7075 based P/M alloys were mixed with %1 grafen powder and pressed and sintered at vacuum condition. After sintering hot swaging were caried out heating specimens at 350 ℃ in a resistance furnace. The tensile strength values of the consolidated bars after T6 heat treatment is in the range of 345-431MPa inspite of local agglomerations in the alloy matrix. Wear depth measured at 10N load for graphene added composites revealed 150μm wear which is less than graphite added composites have 250μm measured value.

The aim of this reseach is to develop graphene/graphite added AA7075 alloy matrix composite material for different applications such as piston ring bearing to improve solid lubrication. A series of 7075 composite powder alloys were prepared with 1% graphene were mixed, cold pressed and sintered under vacuum condition. After sintering hot swaging experiments were performed preheated at 350 °C in a rezistance furnace deforming flat cross sections into round bars. T6 heat treatment were applied to hot swaged speciments. Altough the composite microstructures consist of local agglomerations in the matrix. Tensile strength values measured at room temperature are in the range of 345-431MPa.

Among the same group specimens tested at 10N load wear depth measured for graphene added composites is 150μm but graphite added composites’ wear depth measured is 250μm. In other words graphene added ones revealed less wear compare to graphite added 7075 matrix composites.

Keywords: Powder aluminum alloy; Graphene; Graphite; Hot forging; Swaging; Vacuum sintering