Comparative study of creep of the die-cast Mg-alloys AZ91, AS21, AS41, AM60 and AE42

The creep resistance of five high-purity die-cast Mg-Al-alloys was investigated in uniaxial compression at temperatures from 70 to 150 degreesC. The evolution of deformation resistance under creep conditions is described as a function of strain epsilon. The work hardening in primary creep determines the times for creep by strains <0.01. Among the investigated alloys AZ91 has the highest creep resistance with the exception of AS41 at stresses below 130 MPa, The microstructural origin of the creep resistance of Mg-Al-alloys is discussed in terms of work hardening by dislocations and hardening by creep-induced precipitation. (C) 2001 Elsevier Science B.V. All rights reserved.