The mechanical properties of steel are influenced by grain size, which can change through mechanisms such as nucleation and growth at elevated temperatures. However, the classic Johnson-Cook model that is widely used in hot deformation simulations does not consider the effect of grain size on flow stress. In this study, the Johnson-Cook model was modified to incorporate the effects of austenite grain size on flow stress. A finite element model was employed to characterize the effects of grain size on the flow stress for different steel grades over a range of temperatures (900⁰ to 1300⁰). Simulation results show good agreement with experimental observations.

Meeting Name

AISTech 2020 (2020: Aug. 31-Sep. 3, Cleveland, OH)


Materials Science and Engineering

Second Department

Mechanical and Aerospace Engineering

Research Center/Lab(s)

Peaslee Steel Manufacturing Research Center

Second Research Center/Lab

Center for High Performance Computing Research


This work was supported by the Peaslee Steel Manufacturing Research Center (PSMRC) at Missouri University of Science and Technology.

Keywords and Phrases

Johnson-Cook Model; Thermo-mechanical characterization; Prior-austenitic grain size; Finite-Element model

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 2020 Association for Iron & Steel Technology (AIST), All rights reserved.

Publication Date

03 Sep 2020