Filtern
Erscheinungsjahr
Dokumenttyp
- Beitrag zu einem Sammelband (25) (entfernen)
Referierte Publikation
- nein (25)
Schlagworte
- Laser-GMA-hybrid welding (3)
- AISI 304L (2)
- Hydrogen embrittlement (2)
- Metal cored wire electrode (2)
- 1.4306 (1)
- 1.4565 (1)
- 3D-Dehnungsanalyse (1)
- Aluminium alloy (1)
- DVS-Richtlinie 1006 (1)
- Dehngeschwindigkeit (1)
Risssicherheit von Schweißnähten an Pipelines der Offshore-Industrie aus supermartensitischem Stahl
(2005)
Up to the present, the thermomechanical loads during welding and subsequent cooling under design-specific shrinkage restraint resulting from the interaction between the materials and the structure have often not been taken into consideration approperiately for weldability assessment of components. As compared to previous investigations using small specimens this report presents component weld tests under varying intensities of restraint. Online records of the reaction forces and moments demonstrate in which way the intensity of restraint affects the reaction stresses and moments and their meaning for the evaluation of the load level in welded components.
Aspects of positional laser-GMA-hybrid welding using high alloyed tubular cored wire electrodes
(2008)
Anwendung des neuen Controlled Tensile Weldability (CTW) Tests zur Untersuchung der Heißrissneigung
(2006)
High strength structural steels are susceptible to hydrogen embrittlement. A critical combination of stress, amount of diffusible hydrogen and microstructure is believed to cause cold cracking. Especially during welding of high strength structural steels high tensile residual stresses may develop. Therefore, a feasibility study was conducted using synchrotron X-ray diffraction in order to analyze the stress–strain behavior during tensile loading. For that purpose two types of steel showing different hardening mechanisms were used. On the one hand a thermo-mechanically treated S1100MC and on the other hand a quenched and tempered S1300Q were chosen. The samples were electrochemically charged with hydrogen and subsequently stored in liquid nitrogen to prevent effusion. Tensile tests of the samples were conducted in a special load frame allowing for tilting the samples while applying constant loads. High energy synchrotron radiation was used for energy dispersive X-ray diffraction (EDXRD) analysis in transmission geometry. This method offers the possibility for measuring several diffraction lines of all contributing crystalline phases of the material. Strains as well as stresses applying the sin²ψ-method were determined for varying load situations. This feasibility study shows how the interaction of hydrogen and the stress/strain response may be assessed by diffraction methods. Examples are presented showing that hydrogen alters the load distribution as well as the strain behavior between different lattice planes in high strength steels.
Hydrogen embrittlement (HE) is a widely known phenomenon and under investigation already for more than a century. This phenomenon, though thoroughly studied, is not yet completely understood, and so far, there are several suggested mechanisms that try to explain the occurrence of HE. One important factor of understanding the HE phenomenon and predicting hydrogen-assisted failure is the descent knowledge about the hydrogen transport behaviour in the material. Neutron radiography is a proven method for tracking hydrogen diffusion and it was applied successfully in various research studies. In the presented study, we examined the hydrogen effusion behaviour in duplex stainless steel by means of neutron radiography and calculated the effective diffusion coefficient from the obtained transmission images.