Creep behavior of an Al-6061 metal matrix composite produced by liquid metallurgy processing

Constant stress creep tests were conducted on an Al-6061 metal matrix composite reinforced with alumina microspheres and produced using liquid metallurgy processing. By introducing a threshold stress into the creep analysis, it is concluded that creep occurs by viscous glide in the matrix with a stress exponent of ≈ 3 and an activation energy of ≈125 kJ mol−1. The threshold stress is probably associated with the presence of fine spinel crystals which have been identified in the matrix of the composite.