| Al/AlN particulate composites were prepared by mechanical alloying (MA) of Al powder in NH3 or N2 atmosphere. The AlN phase formed only by a combination of MA in NH3 and subsequent sintering. To improve the mechanical properties of the resulting Al/AlN bimodal composites, the mechanically alloyed Al powder was mixed with pristine Al powder and sintered. This resulted in (Al/AlN)/Al trimodal particulate composites with interesting properties. The outer part of the composites was hardened during sintering, showing the possibility of surface hardening by simple sintering in Al alloys. |
full paper (pdf, 448 Kb)