Hardening and softening in an Mg–Al–Ca matrix alloy reinforced with short graphite fibres

Abstract The mechanical properties of an AX41 magnesium alloy (4Al-1Ca-balance Mg; in wt.%) reinforced with Sigrafil C40 fibres were investigated. Compression tests were conducted at temperatures between 23 and 300 °C at a strain rate of 8.3 · 10 – 5 s – 1 . The yield stress and the maximum stress decrease with increasing testing temperature. The influence of the reinforcement on both characteristic stresses becomes weaker with increasing temperature. At higher temperatures, no significant work hardening was observed. The results indicate the occurrence of dynamic recovery. Possible hardening and softening mechanisms are discussed.