Prediction of the yield strength of a secondary-hardening steel

Based on detailed three-dimensional (3-D) local-electrode atom-probe (LEAP) tomographic measurements of the properties of Cu and M2C precipitates, the yield strength of a high-toughness secondary-hardening steel, BA160, as a function of aging time is predicted using a newly developed 3-D yield strength model. Contributions from each strengthening constituent are evaluated with the model, and superposition laws are applied to add each contribution. Prediction of the yield strength based entirely on 3-D microstructural information is thus achieved. The accuracy of the prediction depends on the superposition laws and the LEAP tomographic measurements, especially the mean radius and volume fraction of M2C precipitates. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.