Rao, J.; Payton, E. J.; Somsen, C.; Neuking, K.; Eggeler, G.; Kostka, A.; dos Santos, J. F.: Where Does the Lithium Go? – A Study of the Precipitates in the Stir Zone of a Friction Stir Weld in a Li-containing 2xxx series Al Alloy. Advanced Engineering Materials 12 (4), pp. 298 - 303 (2010)
Barbatti, C.; Garcia, J.; Pinto, H.; Kostka, A.; Di Prinzio, A.; Staia, M.; Pitonak, R.; Pyzalla, A. R.: Influence of micro-blasting on the microstructure and residual stresses of CVD κ-Al2O3 coatings. Surface and Coatings Technology 203 (24), pp. 3708 - 3717 (2009)
Coelho, R. S.; Kostka, A.; Pinto, H.; Rothkirch, A.; Pyzalla, A. R.; Dos Santos, J.: Microstructure and Residual Stress Formation in an AA6040 to AZ31B Friction Stir Weld. Advances in X-Ray Analyses 52, pp. 360 - 367 (2009)
Kostka, A.; Coelho, R. S.; dos Santos, J.; Pyzalla, A. R.: Microstructure of friction stir welding of aluminium alloy to magnesium alloy. Scripta Materialia 60, pp. 953 - 956 (2009)
Coelho, R. S.; Kostka, A.; dos Santos, J.; Pyzalla, A. R.: ESBD technique visualization of material flow in aluminium to steel friction-stir dissimilar welding. Advanced Engineering Materials 10 (12), pp. 1127 - 1133 (2008)
Barbatti, C.; Garcia, J.; Sket, F.; Kostka, A.; Pyzalla, A. R.: Influence of nitridation on surface microstructure and properties of graded cemented carbides with Co and Ni binders. Surface and Coating Technology 292, pp. 5962 - 5975 (2008)
Coelho, R. S.; Kostka, A.; Pinto, H.; Riekehr, S.; Kocak, M.; Pyzalla, A. R.: Microstructure and Mechanical Properties of Magnesium Alloy AZ31B Laser Beam Welds. Material Science and Engineering A 485, pp. 20 - 30 (2008)
Coelho, R. S.; Kostka, A.; Pinto, H.; Riekehr, S.; Kocak, M.; Pyzalla, A. R.: Microstructure and Residual Stresses in Dissimilar Mg–Al–Zn-alloy Single Overlap Laser Beam Welds. Materials Science Forum 571-572, pp. 361 - 366 (2008)
Coelho, R. S.; Kostka, A.; Sheikhi, S.; dos Santos, J.; Pyzalla, A. R.: Microstructure and Mechanical Properties of an AA6181-T4 Aluminium Alloy to HC340LA High Strength Friction Stir Overlap Weld. Advanced Engineering Materials 10 (10), pp. 961 - 972 (2008)
Kostka, A.; Tak, K.-G.; Eggeler, G.: On the effect of equal-channel angular pressing on creep of tempered martensite ferritic steels. Materials Science and Engineering A 481-482, pp. 723 - 726 (2008)
Dumont, M.; Pyzalla, A. R.; Kostka, A.; Borbély, A.: Characterization of sauropod bone structure. In: Biology of the sauropod dinosaurs: understanding the life of giants, pp. 150 - 169 (Eds. Klein, N.; Remes, K.; Sander, P.M.). Indiana University Press, Bloomington and Indianapolis (2011)
dos Santos, J. F.; Olea, C. A. W.; Coelho, R. S.; Kostka, A.; Paglia, C. S.: Metallurgy and weld performance in friction stir welding. In: Friction stir welding: From basics to applications, pp. 1 - 436 (Eds. Lohwasser, D.; Chen, Z.). Woodhead Publishing Limited incorporating Chandos Publishing, Cambridge, UK (2009)
Hammerschmidt, T.; Koßmann, J.; Zenk, C. H.; Neumeier, S.; Göken, M.; Lopez-Galilea, I.; Mújica Roncery, L.; Huth, S.; Kostka, A.; Theisen, W.et al.; Drautz, R.: The role of local chemical composition for TCP phase precipitation in Ni-base and Co-base superalloys. In: Proceedings of the International Symposium on Superalloys, Vol. 2016, pp. 89 - 96. 13th International Symposium on Superalloys, SUPERALLOYS 2016; Seven Springs Mountain ResortSeven Springs, Seven Springs, PA, USA, September 11, 2016 - September 15, 2016. Minerals, Metals and Materials Society, Pittsburgh, PA, USA (2016)
Springer, H.; Aparicio-Fernández, R.; Duarte, M. J.; Zhang, H.; Baron, C.; Kostka, A.; Raabe, D.: Alloy design and processing routes for novel high modulus steels. In: PTM 2015 - Proceedings of the International Conference on Solid-Solid Phase Transformations in Inorganic Materials 2015, p. 981 (Eds. Chen, L.-Q.; Militzer, M.; Botton, G.; Howe, J.; Sinclair, C. W. et al.). International Conference on Solid-Solid Phase Transformations in Inorganic Materials 2015, PTM 2015, Whistler, BC, Canada, June 28, 2015 - July 03, 2015. PTM 2015, Whistler, British Columbia (2015)
Naraparaju, R.; Christ, H.-J.; Renner, F. U.; Kostka, A.: Dislocation Engineering and its effect on the oxidation behaviour. Materials at High Temperatures 29, pp. 116 - 122 (2012)
Ponge, D.; Millán, J.; Dmitrieva, O.; Sander, B.; Kostka, A.; Raabe, D.: Ultra high strength steel design by using nanoparticles. In: Proceedings Book 2nd Inter. Symp. Steel Science ISSS 2009 (Ed. K, H. N.T.). Proceedings 2nd Inter. Symp. Steel Science ISSS 2009, Kyoto, Japan, October 21, 2009 - October 24, 2009. The Iron and Steel Institute of Japan, Japan (2009)
Garcia, J.; Lammer, A.; Garcia, L. F.; Weber, S.; Kostka, A.; Pyzalla, A. R.: Investigations of Wear Mechanisms in Diamond Tools with Fe-Based Matrices Reinforced with WC-Co Particles. Int. Symposium on Friction, Wear and Wear Protection, Aachen, Germany, April 09, 2008 - April 11, 2008. (2008)
Hydrogen in aluminium can cause embrittlement and critical failure. However, the behaviour of hydrogen in aluminium was not yet understood. Scientists at the Max-Planck-Institut für Eisenforschung were able to locate hydrogen inside aluminium’s microstructure and designed strategies to trap the hydrogen atoms inside the microstructure. This can…
For understanding the underlying hydrogen embrittlement mechanism in transformation-induced plasticity steels, the process of damage evolution in a model austenite/martensite dual-phase microstructure following hydrogenation was investigated through multi-scale electron channelling contrast imaging and in situ optical microscopy.
We will investigate the electrothermomechanical response of individual metallic nanowires as a function of microstructural interfaces from the growth processes. This will be accomplished using in situ SEM 4-point probe-based electrical resistivity measurements and 2-point probe-based impedance measurements, as a function of mechanical strain and…
Hydrogen induced embrittlement of metals is one of the long standing unresolved problems in Materials Science. A hierarchical multiscale approach is used to investigate the underlying atomistic mechanisms.
Hydrogen embrittlement affects high-strength ferrite/martensite dual-phase (DP) steels. The associated micromechanisms which lead to failure have not been fully clarified yet. Here we present a quantitative micromechanical analysis of the microstructural damage phenomena in a model DP steel in the presence of hydrogen.
This project will aim at developing MEMS based nanoforce sensors with capacitive sensing capabilities. The nanoforce sensors will be further incorporated with in situ SEM and TEM small scale testing systems, for allowing simultaneous visualization of the deformation process during mechanical tests
The project aims to study corrosion, a detrimental process with an enormous impact on global economy, by combining denstiy-functional theory calculations with thermodynamic concepts.
Understanding hydrogen-assisted embrittlement of advanced structural materials is essential for enabling future hydrogen-based energy industries. A crucially important phenomenon in this context is the delayed fracture in high-strength structural materials. Factors affecting the hydrogen embrittlement are the hydrogen content,...
Thermo-chemo-mechanical interactions due to thermally activated and/or mechanically induced processes govern the constitutive behaviour of metallic alloys during production and in service. Understanding these mechanisms and their influence on the material behaviour is of very high relevance for designing new alloys and corresponding…