Powder metallurgy of Al-based composites reinforced with Fe-based glassy particles: Effect of microstructural modification

ABSTRACT

Al metal matrix composites reinforced with high volume fraction of Fe_50.1Co_35.1Nb_7.7B_4.3Si_2.8 glassy particles were fabricated by mechanical milling followed by hot pressing. Elemental Al powders blended with 60 vol.% of glassy particles were mechanically milled for 1, 5, 10, 15, and 20 h, respectively. Selected samples were sintered by uniaxial hot pressing under Ar atmosphere. The changes in the microstructure along with their mechanical properties were investigated. Structural and microstructural characterization followed by microhardness and compression test results of the bulk composite material is reported. The use of high volume fraction of Fe-based glassy particles as reinforcement led to significant hardening of the Al matrix while leading to a remarkable combination of high strength and plasticity.

KEYWORDS:

• Al matrix composites
• Al powders
• glassy particles
• hot pressing
• mechanical milling
• microstructure

Acknowledgments

The authors would like to thank Dr V. Uhlenwinkel for providing the gas-atomized powder.