| Abstract Scope |
In the first part of the presentation, we show that typically brittle quasicrystals can exhibit remarkable ductility of over 50% strains and high strengths of ∼4.5 GPa at room temperature and sub-micrometer scales. In contrast to the generally accepted dominant deformation mechanism in quasicrystals—dislocation climb, our observation suggests that dislocation glide may govern plasticity under high-stress and low-temperature conditions. In the second part of the presentation, we present that the fracture properties of high-entropy alloys (HEAs). Most refractory HEAs are brittle and suffer from limited formability at ambient temperature. Here, using in situ micro-cantilever tests, we show that the fracture toughness of a bi-crystal HEA is one order of magnitude lower than that of single crystalline ones. In addition, we have documented and described aspects of mud-cracking specific to Cr-containing electrodeposited HEA alloys made from trivalent Cr electrolytes. |