Segregation of Mo atoms into stacking faults in CrFeCoNiMo alloy

ABSTRACT

Solute segregation at dislocations can impede the motion of dislocations, strengthening materials. Here, we study the formation and role of solute segregation at dislocations in CrFeCoNiMo high-entropy alloys (HEAs) by high-angle annular dark-field scanning transmission electron microscopy imaging and mechanical testing both deformed and annealed samples. Mo atoms exhibit pronounced segregation into the planar-extended core of dislocations, i.e. stacking faults, causing the increase in the yield strength while the loss of the ductility. This work suggests that mechanical properties of HEAs can be tailored by alloying additional elements that are in favour of segregation into dislocations.

KEYWORDS:

• High-entropy alloys
• segregation
• strengthening
• stacking faults

ORCID

Jian Wang http://orcid.org/0000-0001-5130-300X

Additional information

Funding

This work is supported by the Science Fund for Creative Research Groups [grant number 61271043]. J.W. acknowledges finical support provided by the Research Council at the University of Nebraska-Lincoln. K.S.M. gratefully acknowledges the financial support for his study in University of Nebraska-Lincoln as a joint PhD student by the China Scholarship Council (File No. 201706020019).