Calculation models for determining the critical points of steel

Prediction of Ac₃ and Martensite Start Temperatures by a Data-driven Model Selection Approach

“…Hoheok KIM, 1) * Junya INOUE, 1,2) Masato OKADA 3) and Kenji NAGATA 3) 1) Graduate School of Materials Engineering, The University of Tokyo, 7-3-1 Bunkyo, Hongo, Tokyo, 113-8656 Japan.…”

“…(Received on April 13, 2017; accepted on August 2, 2017) Four different information criteria, which are widely used for model selection problems, are applied to reveal the explanatory variables for phase transformation temperatures of steels, austenitise temperature (Ac 3 ) and martensite-start temperature (Ms). Using existing datasets for CCT diagram for various steels, the predictive equations for these critical temperatures are derived.…”

“…Using existing datasets for CCT diagram for various steels, the predictive equations for these critical temperatures are derived. A number of empirical equations have been proposed to enable efficient prediction of the the Ac 3 and Ms temperatures of steels. However, the key parameters in those equations are usually chosen based on researchers' trials and errors.…”

“…Therefore, various empirical models have been proposed and the most commonly used equations among those are listed in Table 1. [1][2][3][4][5][6][7] All these equations were derived by the multivariate regression analysis using large experimental datasets composed of several tens or hundreds of steels with various chemical compositions.…”

A new optimization procedure for the accurate characterization of thermal phase transformation curves based on controlled quenching experiments

“…The transformation kinetics can be predicted with the Kirkaldy method [10,11], after the characteristic temperatures of phase change are estimated. The austenitization-end temperature (A C3) is averaged over the estimation method from Andrews [12] and Kasatkin [13]. Both are based on the chemical composition.…”