Effects of Microalloy Additions and Thermomechanical Processing on Austenite Grain Size Control in Induction-Hardenable Medium Carbon Steel Bar Rolling

Abstract:

Three AISI 1045 steels: a base steel, one modified with vanadium (V), and one modified with V and niobium (Nb) were studied to evaluate microstructural conditioning prior to induction hardening. Simulated bar rolling histories were evaluated using fixed-end hot torsion tests with a Gleeble® 3500. The effects of chemical composition and thermomechanical treatment on final microstructures were examined through analysis of laboratory simulations of steel bar rolling and induction hardening processes in order to provide additional insights into the morphological evolution of austenite of microalloyed steels. Analysis of prior austenite grain size (PAGS) is complemented with analysis of austenite recrystallization and pancaking during rolling. The potential for utilizing TMP, in conjunction with microalloy additions, to enhance bar steel microstructures and subsequent performance is assessed by evaluating the induction hardening response of each steel systematically processed with different preconditioning treatments.

• Periodical: Materials Science Forum (Volume 879)
• Pages: 2094-2099
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.879.2094
• Online since: November 2016
• Authors: B.M. Whitley*, John G. Speer, R.L. Cryderman, R.C. Goldstein, K.O. Findley, David K. Matlock
• Keywords: Austenite Conditioning, Hot Torsion, Induction Hardening, Microalloy, Physical Simulation, Prior Austenite Grain Size, THERMOMECHANICAL PROCESSING

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