Control of Microstructure by MaxStrain Device

Grain refinement should increase strength of metallic materials in a predictable manner. However, in applications of severe plastic deformations for this purpose, limits have been observed due to self-recovery and strain-induced precipitation assisted by generation of adiabatic heat. Pure metals and single-phase alloys have not been the best candidates for achieving ultrafine-grained microstructures therefore more often precipitation-hardening multi-phase alloys have been used in SPD experiments. To generate ultrafine-grained microstructures by accumulated multiple compressive strains executed at various strain rates during programmed thermal cycles the MaxStrainTM device was developed for GleebleTM physical simulator. This paper deals with processing of Al-6061 wrought alloy and Al-319 cast alloy by the MaxStrain device, and describes obtained microstructures.