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The mechanical behavior of AlSi10Mg produced by selective laser melting (SLM) and heat treated to T5 and T6 was investigated under uniaxial compressive, tensile and combined shear-compression loading for strain rates up to 2·103s−1 and different temperatures (23 °C/400 °C). AlSi10Mg-T5 possess lower strength but higher elongation to fracture, higher specific absorbed mechanical energy and higher strain rate sensitivity as the T6 condition. In addition, the material in the T6 state was found to be more prone to biaxial loading and elevated temperature than the T5 state. The microstructural and fractographical investigation reveal that these differences are mainly related to different sizes and species of precipitates. The study is complemented by a constitutive description of the flow stress as function of strain and strain rate for the whole range of strain rates. This model is based on the Orowan equation including dislocation drag mechanism in combination with the well-known Kocks-Meckin-Esrin approach. With this modelling it was shown that typical length scales, mobile/total dislocation densities and dislocation generation/annihilation significantly differ as function of strain.

Due to the continued interest in reducing weight in both automobile and aerospace structures, interest has grown in magnesium based alloys as a possible materials solution. Despite this interest, these alloys have not been widely utilized due to their relatively poor mechanical properties in comparison to other material systems. However, recent research has clearly indicated that improved mechanical properties can be achieved in these alloys through the use of severe plastic deformation processing methods. In this report, we examine the influence of equal channel angular pressing on the mechanical response of Elektron 675, a Mg–Gd–Y alloy. Results indicate that an appreciable increase in total elongation and absorbed energy can be obtained depending on the selected processing route. However, these improvements in elongation are somewhat offset by a slight reduction in tensile strength. The observed mechanical response is explained through microstructural analysis as well as texture measurements.