Production and characterization of in situ Al4C3 reinforced aluminum-based composite produced by mechanical alloying technique

In this study, aluminum powders were mixed with carbon black and mechanically alloyed in a high-energy ball mill for up to 30 h under argon atmosphere. XRD results showed that no Al4C3 formed during the mechanical alloying (MA) process. Mechanically alloyed powders were then compacted at 650 MPa pressure to produce transverse rupture blanks. These blanks were then sintered at 600 and 650 degreesC for 5, 10 and 20 h under argon atmosphere. X-Ray diffraction analysis of the sintered blocks showed the presence of Al4C3 phase. Increasing MA processing time, sintering temperature and duration, resulted in an increase in the amount of Al4C3 phase. XRD and SEM analysis showed that the most Al4C3 transformation occurred in the blank, which was mechanically alloyed for 30 h and sintered for 20 h at 650 degreesC. The highest hardness value (347 Hv) was obtained in this blank. Transverse rupture strengths of the sintered blanks were between 6.32 and 234.16 MPa. The highest value was obtained for the blank, which was mechanically alloyed for 15 h and sintered for 20 It at 650 degreesC. (C) 2003 Elsevier Ltd. All rights reserved.