Al-Zn alloys with different Zn concentrations between 2 and 30 wt.% were processed by high-pressure torsion (HPT) to produce ultrafine-grained (UFG) materials. Microstructural and mechanical and properties of these UFG alloys were then investigated using depth-sensing indentations (DSI), focused ion beam (FIB), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Emphasis was placed on the decomposition due to the HPT process, as well as on its effects on the mechanical properties of the UFG alloys. For low Zn contents, HPT gave strengthening due to grain refinement while for the highest Zn concentration the decomposition of the microstructure yielded an abnormal softening at room temperature. The microstructure decomposition led also to the formation of a Zn-rich phase, which wets the Al/Al grain boundaries and enhanced the role of grain boundary sliding with unusually high strain rate sensitivity. The occurrence of intensive sliding in these UFG alloys at room temperature is demonstrated by deforming micro-pillars, illustrating a potential for the effective application of these UFG materials in micro-devices.
|Journal||IOP Conference Series: Materials Science and Engineering|
|Publication status||Published - nov. 4 2019|
|Event||5th International Conference on Competitive Materials and Technology Processes, IC-CMTP 2018 - Miskolc-Lillafured, Hungary|
Duration: okt. 8 2018 → okt. 12 2018
ASJC Scopus subject areas
- Materials Science(all)