Abstract
An Al-based composite powder (Al-2%C) was prepared by mechanical alloying (MA). Mixed powders were cold compacted and annealed using two consecutive treatments. Microstructure progresses in both; the as-milled and the as-pressed and annealed conditions were characterized by X-ray diffractometry (XRD) and transmission electron microscopy (TEM). During MA, C diffused into Al to form a solid solution. However, for MA, primary compaction and 1 hour sintering at 650 °C was insufficient to synthesize Al with C. Only after secondary pressing and long-time annealing at 550 °C, fine precipitates of Al₄C₃ were formed throughout the matrix. Increase in Al₄C₃ dispersion and stabilization of a dense dislocation substructure was the main source of systematic rise in both electric resistivity and hardness

Key words
mechanical alloying, synthesizing, Al₄C₃ precipitation, electrical resistivity

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