| Description: |
Method of obtaining of cast composite materials (CCM) on the basis of aluminum reinforced by σ-phase (FeCr) is proposed. The wear rate of specimens from CCM is depended on the height of casting, which these specimens were cut out from. The average size of particles FeCr 27.5-35.5 µm and their quantity 184-263 pieces/mm 2 make the greatest positive influence on wear rate of CCM under dry friction. INTRODUCTION Aluminum alloys, due to their unique characteristics, are widely used in many branches of industries (automotive, aerospace industry etc.). For improvement of service characteristic of aluminum alloys basically three technologies allowing to obtain composite materials (CM) on the basis of aluminum are used: powder metallurgy, mechanical dispersion, and impregnation. All these processes are effective enough, but demand significant expenses. Shynsky has offered [1] a method of obtaining of cast composite materials (CCM) on the basis of aluminum (Al-FeCr) by means of Lost-Foam Process [2]. In this case the reinforced σ-phase (FeCr) is implanted in gasification pattern made of polystyrene foam and then, at horizontal casting it is distributed in volume of casting. By means of this process a cast composites (Al-10FeCr) were obtained. It is experimentally established [3] that by the filling of the mould by means matrix melt an arise both the convection and turbulent streams take place, which due to the temperature gradient and the hydrodynamic of process cause. These streams are the reason of non-uniform distribution of dispersed phase in matrix melt that, probably, can influence on tribological characteristics of reinforced CCM of system Al-FeCr. With this purpose the wear rate of samples from the CCM cut out from various height of casting are investigated. |