Mechanical Behavior at the Nanoscale VI: On-Demand Poster Session
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS Structural Materials Division, TMS: Computational Materials Science and Engineering Committee, TMS: Mechanical Behavior of Materials Committee, TMS: Nanomechanical Materials Behavior Committee
Program Organizers: Matthew Daly, University of Illinois-Chicago; Douglas Stauffer, Bruker Nano Surfaces & Metrology; Wei Gao, University of Texas at San Antonio; Changhong Cao, McGill University; Mohsen Asle Zaeem, Colorado School of Mines

Monday 8:00 AM
March 14, 2022
Room: Nanostructured Materials
Location: On-Demand Poster Hall

Correlation of Crack Propagation with Mechanical Properties of Parent Phases and Softened Phases in Bearing Steels under Rolling Contact Fatigue: Eunji Song1; Hansol Jeon1; Ju-Young Kim1; 1UNIST
     Bearing steels are components used under rolling contact fatigue. Even though rolling contact transfers stress less than yield strength, crack propagation is observed after rolling contacts more than hundreds of thousands. It was reported that decrease of micro-hardness and transition of martensite phases to tempered and ferrite phases are observed with increasing rolling cycles. The widely known cause for decrease of micro-hardness and microstructure transition is dislocation-assisted carbon migration, which is called as mechanical tempering. Here, we focused on disparity of mechanical properties between parent phases and softened phases as a cause for strain concentration.In this study, tensile properties of constituent phases and crack phenomenon are estimated on S55Cr after 0, 5*103, 5*104, 5*105, and 5*107 cycles of rolling contact fatigue. We discuss disparity in mechanical properties between parent phases and softened phases and crack nucleation sites with increasing rolling cycles.