Optical Detection of Phase Transformations in Steels: An Innovative Method for Time-Efficient Material Characterization During Tailored Thermo-mechanical Processing of a Press Hardening Steel

Metallurgical and Materials Transactions A - With an innovative optical characterization method, using high-temperature digital image correlation in combination with thermal imaging, the local...     

Assessment of subcritical crack growth in hydrogen-containing environment by the parameters of acoustic emission signals

Estimation models (differential equations, initial and final conditions) for determining the crack propagation kinetics in hydrogen-containing environments using the acoustic emission (AE) signal parameters are proposed. The formulation of these models is based on the main ideals of the AE method, dependence between the crack increment area and a sum of AE-signals amplitude, main criteria of fracture mechanics and laws of thermodynamics.     

A global renewable energy system: A modelling exercise in ETSAP/TIAM

This paper aims to test the ETSAP²-TIAM global energy system model and to try out how far it can go towards a global 100% renewable energy system with the existing model database. This will show where limits in global resources are met and where limits in the data fed to the model until now are met.     

Efficient Modelling and Simulation of Process Chains in Sheet Metal Forming and Processing

The ultimate aim of this work is the development of methods for the simulation of manufacturing process chains such as forming→cutting→heat treatment→joining, providving maximal efficiency without significant loss of accuracy. In the current work, we make the first step in this direction by considering the case of forming of the new high strength steel LH®800. The work begins with a characterization and metallographic investigation of this new steel. Following this, a combined hardening model appropriate for this steel is formulated and identified. The identified model is then validated with the help of the finite‐element simulation of draw‐bending. On this basis, the model was then used to simulate cup deep‐drawing. This process was also simulated with a so‐called one‐step solver which is much faster than the finite element simulation. The results of these two simulations are compared with the results of the deep‐drawing experiment.