TY - CONF A1 - Mente, Tobias T1 - Mesoskalensimulation zweiphasiger Gefüge unter Nutzung hochenergetischer Beugungsexperimente T2 - MDDK - Master-, Diplomanden-, Doktorandenkolloqium CY - Magdeburg, Germany DA - 2012-01-26 PY - 2012 AN - OPUS4-28131 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Mesoscale Model for Hydrogen Assisted Cracking in Two-Phase Microstuctures T2 - 10th International Seminar Numerical Analysis of Weldability CY - Seggauberg, Austria DA - 2012-09-23 PY - 2012 AN - OPUS4-26781 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Mesoscale Crack Model for Duplex Stainless Steel Microstructures T2 - IIW Intermediate Meeting 2012 CY - Cambridge, England DA - 2012-02-20 PY - 2012 AN - OPUS4-25537 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Wasserstoffunterstützte Rissbildung in geschweißten hochfesten Feinkornbaustählen T2 - 17. LWE Seminar - "Schweißen im Mobilkranbau" CY - Ehingen, Germany DA - 2012-11-08 PY - 2012 AN - OPUS4-27043 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Stand der Technik des Schweißens hoch- und ultrahochfester Feinkornbaustähle T2 - 1st Alform Welding Day CY - Linz, Austria DA - 2012-06-05 PY - 2012 AN - OPUS4-26032 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Numerical simulation of hydrogen assisted cold cracking in welded joints of High strength structural steels T2 - IIW Annual Assembly CY - Denver, CO, USA DA - 2012-07-09 PY - 2012 AN - OPUS4-26164 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mente, Tobias A1 - Böllinghaus, Thomas T1 - Heat treatment effects on the reduction of hydrogen in multi-layer high-strength weld joints N2 - High-strength structural steels with yield strengths up to 1 100 MPa are used in various industrial sectors such as for the construction of cranes, pipelines and offshore structures. However, with increasing strength the ductility and deformation capacities of these materials are reduced and thus, they show an enhanced sensitivity against degradation due to hydrogen with increasing yield strength. It means they become susceptible to hydrogen-assisted cold cracking (HACC) during fabrication welding. In order to avoid such defects, the existing standards recommend preheating and/or interpass temperature, as well as post heat treatments. However, the standards relate only to steels with a maximum yield strength of Rp0.2 = 960 MPa. Hence, in welding these high-strength structural steels with yield strengths up to 1 100 MPa, it is very important to have practical guidelines for determining suitable heat treatment procedures to avoid HACC in welds, in particular in safety-relevant components. As a contribution to the further establishment of suffi cient Hydrogen-Removal Heat Treatments (HRHT), two dimensional numerical models of butt and lap joints of various thicknesses were developed. Hydrogen diffusion and the effect of different post heat treatments upon hydrogen reduction in high-strength structural steel were studied. It turned out that the hydrogen diffusion behaviour in the lap and the butt joints are quite different and that the hydrogen concentration in the lap joint can be reduced signifi cantly faster in comparison to the butt joint KW - Cold cracking KW - Heat treatment KW - High strength steels KW - Hydrogen KW - Numerical simulation KW - Structural steels PY - 2012 SN - 0043-2288 SN - 1878-6669 VL - 56 IS - 7/8 SP - 26 EP - 36 PB - Springer CY - Oxford AN - OPUS4-26055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mente, Tobias A1 - Böllinghaus, Thomas T1 - Modeling of hydrogen distribution in a duplex stainless steel N2 - Quite a number of models for hydrogen distribution in steels and welds have been developed in the past 20 years. They reach from simple analytical models to more complex two and three dimensional finite element simulations. So far, these models have been used to simulate hydrogen distribution in homogeneous microstructure. This paper contributes to numerical simulation of hydrogen distribution in heterogeneous microstructure, e. g. in a duplex stainless steel microstructure consisting of two phase fractions. Under appropriate conditions, such as cathodic protection, it is possible that hydrogen is absorbed leading to material embrittlement and possibly initiating hydrogen assisted cracking. In order to avoid hydrogen assisted cracking in duplex stainless steels, it is of great interest to know more about the diffusion behavior of the ferrite and austenite phase. A numerical model has been developed that operates on the mesoscale and enables simulation of hydrogen transport in the various phases of a metallic material. As a first application of this model, hydrogen distribution in a duplex stainless steel 1.4462, consisting of approximately equal portions of ferrite and austenite, was simulated using the finite element program package ANSYS. The results reflect the dependency of hydrogen distribution on the microstructural alignment of the ferrite and austenite phase fractions. Crack-critical areas can thus be identified, provided the critical strain-hydrogen combination is known for the respective microstructural phase. KW - Finite element KW - Simulation KW - Duplex stainless steel KW - Hydrogen KW - Diffusion KW - Weld metal KW - Microstructure PY - 2012 SN - 0043-2288 SN - 1878-6669 VL - 56 IS - 11/12 SP - 66 EP - 78 PB - Springer CY - Oxford AN - OPUS4-27483 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Numerical Simulation of Hydrogen Assisted Cold Cracking in welded Joints of High Strength Structural Steels T2 - IIW Intermediate Meeting 2012 CY - Cambridge, England DA - 2012-02-20 PY - 2012 AN - OPUS4-25538 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mente, Tobias T1 - Mesoscale Crack Model for Duplex Stainless Steels Microstructures T2 - IIW Annual Assembly CY - Denver, CO, USA DA - 2012-07-09 PY - 2012 AN - OPUS4-26165 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -