Browsing by Author "Broeckmann, C."

Now showing 1 - 2 of 2

Citation - WoS: 46
Citation - Scopus: 51
Multiscale modeling of tempering of AISI H13 hot-work tool steel - Part 1: Prediction of microstructure evolution and coupling with mechanical properties
(Elsevier, 2016) Eser, A.; Broeckmann, C.; Simsir, C.
In the first part of this two part study, the mechanical properties necessary for the simulation of tempering of an AISI H13 (DIN 1.2344, X40CrMoV5-1) tool steel was derived using physically based precipitation simulations and microstructure-property relationships. For this purpose, the precipitation of fine carbides were simulated using a thermo-kinetic software which allows prediction of the evolution of precipitation/dissolution reactions and the particle sizes. Then, those microstructural findings were coupled with physically based microstructure-property models to predict the yield stress, flow curve and creep properties. The predicted mechanical properties were verified with corresponding experiments and a good agreement was found. In the second part of this study, those properties were coupled with a Finite Element (FE) model in order to predict the relaxation of internal stresses and the evolution of deformations at the macroscopic scale. (C) 2015 Elsevier B.V. All rights reserved.
Citation - WoS: 13
Citation - Scopus: 19
Multiscale Modeling of Tempering of Aisi H13 Hot-Work Tool Steel - Part 2: Coupling Predicted Mechanical Properties With Fem Simulations
(Elsevier Science Bv, 2016) Eser, A.; Broeckmann, C.; Simsir, C.
Simulation of austenitization and quenching of steel using the Finite Element Method (FEM) is nowadays a common tool to predict residual stresses and deformations during these processes. However the simulation of tempering, which determines the final residual stresses and distortions has been often neglected or performed in a purely phenomenological and highly simplified way. The objective of this study is to precisely predict the relaxation of internal stresses during tempering, taking explicitly into account the evolution of the microstructure. Mechanical properties which determine the relaxation of stress; namely the drop of the yield stress and the creep mechanism are the key factors for the success of the simulation. These mechanical parameters can be determined experimentally for a specific tempering temperature. However tempering temperature for most steels varies for each industrial application in order to adjust the desired hardness-toughness relation. Consequently, experimentally measurement of decisive mechanical properties which determine the amount of stress relaxation for each tempering temperature is very costly. Therefore, these material parameters were simulated from physically based material models with coupled microstructural simulations in the first part of this two-part investigation. In this part of the study, the simulated mechanical properties will be coupled with the FEM simulations using "Abaqus (R)", in order to simulate the stress relaxation during the tempering process of a thick-walled workpiece made of hot-work tool steel AISI H13 (DIN 1.2344, X40CrMoV5-1). Utilizing this methodology, different tempering conditions (soaking time, tempering temperature) can be considered in the model to predict the stress relaxation in macroscopic scale. (C) 2015 Elsevier B.V. All rights reserved.