Lifetime behaviour of unidirectionally wire reinforced lightweight metal matrix composites

•The fatigue behaviour of a spring steel wire reinforced magnesium alloy is investigated.•The reinforcement leads to an increase in lifetime.•The occurring bridging effect after fatigue of the matrix can be quantified.•The stress strain response leads to a derivation of a universal lifetime model.•This simple lifetime prediction can be enlarged to other MMCs.

In the field of lightweight construction for transportation means, hybrid structures composed of high-strength and low-density materials exhibit a high application potential. The current work shows that a spring steel wire reinforcement content of 11.1 vol.% leads to a significant increase in lifetime of the magnesium alloy AZ31 under stress controlled fatigue loading. Based on the knowledge of the quasi-static behaviour of the single components and the fatigue behaviour of the single matrix material and on the understanding of mechanisms and mechanics of constituent deformation and damage evolution a new model is deduced from the quantitative strain response in order to predict the lifetime for different unidirectionally reinforced material systems.