Abstract

Grain boundary segregation is an important phenomenon for nanocrystalline materials as it influences thermal stability and mechanical properties. While several studies have considered effects of single, intentional segregants, co-segregation of intentional and unintentional segregants to general grain boundaries is not commonly investigated using experimental techniques on the atomic scale. This study utilized aberration-corrected scanning transmission electron microscopy and atom probe tomography to evaluate the grain boundary structure and chemistry of an electroplated and annealed electrodeposited Ni–W alloy. Several phases were observed in the annealed microstructure including elongated nanoscale oxide particles and relatively large impurity carbide phases. Furthermore, grain boundaries regularly exhibited ordered structures, minimal elemental tungsten segregation (intended solute) and impurity carbon segregation (unintentional solute), but moderately high-impurity oxygen segregation (unintentional solute). The unintentional segregated impurities (oxygen and carbon) resulted in a total average grain boundary composition of ~ 10 at.%. The consequence of impurity segregation is discussed in terms of thermal stability and potential mechanical properties.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.