Production and Charactarization of Al-Based MMCp Materials Reinforced By Milled Cu + SiC Powders
AbstractIn this study, the effects of Cu + SiC mixture powders milled at different times on the production of metal matrix composite (MMCP) materials containing Al-Cu alloyed matrix and SiC reinforcement were investigated. For this purpose, 67 wt.% Cu and 33 wt.% SiC powders were milled in a three-dimensional mixing apparatus (Turbula) in a stainless steel vessel with zirconia balls of 15 mm diameter for 5 (M5), 10 (M10) and 15 (M15) hours. The milled mixture powders were mixed in a Turbula for 45 minutes with aluminum powder containing 4.7 wt.% Cu + 2.3 wt.% SiC. This mixtured powder was cold compacted at 20 MPa pressure and then hot pressed at 500 °C under 200 MPa pressure for 30 minutes to produce MMCP materials. Microstructures and phases of MMCP materials produced by powder metallurgy (PM) route were determined by XRD analyzes with SEM / EDS studies. Mechanical and physical properties of MMCP materials were characterized by Brinell hardness, transverse rupture strength (TRS) tests and density measurements. In general, an increase in the mechanical properties has been determined although there is a partial reduction in the density of MMCP materials reinforced with M15 powders. The ratio of the actual density of unprocessed (M0) MMCP material to the theoretical density is 99.5%. However, the density ratios in MMCP reinforced with M10 and M15 were measured as 96.3% and 98.6% respectively. The highest transverse rupture strength (212 MPa) was determined in M15 reinforced MMCP and an increase of about 20% was achieved (Fig. 1). The hardness of the produced composite materials doped M15 was increased by 46% compared with the M0 material (Fig. 2).