A Rationale for SRX Regression Model of Hot-Deformed Austenite Using an Orthogonal Taguchi L8 Matrix Steels

Abstract:

In recent past, a linear regression model to predict the activation energy (Qrex) and kinetics of static recrystallisation for hot-deformed austenite was developed based on stress relaxation test results of over 40 different carbon steels. The model is able to predict satisfactorily the static recrystallisation (SRX) kinetics of common carbon steel grades (including microalloyed steels) and also several special steel grades. In this study, the main effects of seven alloying elements, viz., C, Mn, Cr, Ni, Mo, Nb and V, on the activation energy of recrystallisation were further examined by using eight experimental steels based on an orthogonal Taguchi L8 matrix. All steels contained constant additions of B, Ti and Si. Even though originally intended for studies on phase transformation characteristics and hardenability under direct quenching conditions, the L8 matrix steels were suitably employed for further validation of the SRX regression model. In addition, the SRX characteristics and kinetics of a set of new steel compositions including C-Mn, C-Mn-Nb and C-Mn-Nb-Ti types were examined in the light of model equations, which further confirm the suitability of the regression model.

• Periodical: Materials Science Forum (Volumes 715-716)
• Pages: 751-757
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.715-716.751
• Online since: April 2012
• Authors: Mahesh Chandra Somani, L. Pentti Karjalainen
• Keywords: Activation Energy, Austenite, Composition Effects, Regression Modelling, Static Recrystallization, Stress Relaxation, Taguchi L8 Matrix

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