Effect of grain architecture on the ductility in ultrafine grained and nanocrystalline SPD materials

Project Leader: Reinhard Pippan

The goal is to shed more light on the effect of grain architecture including grain shape, shape texture of grains and crystallographic texture, grain size and grain size distribution, grain boundary structure – on ductility and fracture toughness in ultrafine grained and nanocrystalline materials generated by SPD. The results will deliver a base for the improvement of ductility and fracture toughness of these novel materials for structural as well as for functional applications.

1. Hohenwarter Anton, Pippan Reinhard, A comprehensive study on the damage tolerance of ultrafine-grained copper. Materials Science and Engineering A 540, (2012) 89-96.
2. Rathmayr Georg B., Pippan Reinhard, Extrinsic and intrinsic fracture behavior of high pressure torsion deformed nickel. Scripta Materialia 66, (2012) 507-510.
3. Renk Oliver, Hohenwarter Anton, Pippan Reinhard, Cyclic Deformation Behavior of a 316L Austenitic Stainless Steel Processed by High Pressure Torsion. Advanced Engineering Materials 14, (2012) 948-954.
4. Bachmaier Andrea, Pippan Reinhard, Generation of metallic nanocomposites by severe plastic deformation. International Materials Reviews 58, (2013) 41-62.
5. Hohenwarter Anton, Pippan Reinhard, Fracture of ECAP-deformed iron and the role of extrinsic toughening mechanisms. Acta Materialia 61, (2013) 2973-2983.
6. Kammerhofer Christoph, Hohenwarter Anton, Scheriau Stephan, Brantner H.P., Pippan Reinhard, Influence of morphology and structural size on the fracture behavior of a nanostructured pearlitic steel. Materials Science & Engineering A 585, (2013) 190-196.
7. Krawczynska Agnieszka Teresa, Lewandowska Malgorzata, Pippan Reinhard, Kurzydlowski Krzysztof, The Effect of High Pressure Torsion on Structural Refinement and Mechanical Properties of an Austenitic Stainless Steel. Journal of Nanoscience and Nanotechnology 5, (2013) 3246-3249.
8. Rathmayr Georg B., Bachmaier Andrea, Pippan Reinhard, Development of a New Testing Procedure for Performing Tensile Tests on Specimens with Sub-Millimetre Dimensions. Journal of Testing and Evaluation 41, (2013) 1-12.
9. Rathmayr Georg B., Pippan Reinhard, Influence of grain shape and orientation on the mechanical properties of high pressure torsion deformed nickel. Materials Science & Engineering A 560, (2013) 224-231
10. Sabirov Ilshat, Pippan Reinhard, About application of three dimensional analyses of fracture surfaces in fracture study on nanostructured titanium. Computational Materials Science 76, (2013) 72-79
11. O. Renk, A. Hohenwarter, S. Wurster, R. Pippan, Direct evidence for grain boundary motion as the dominant restoration mechanism in the steady-state regime of extremely cold-rolled copper Acta Materialia 77, (2014) 401 - 410.
12. X. Sauvage, Y. Champion, R. Pippan, F. Cuvilly, L. Perrière, A. Akhatova, O. Renk  Structure and properties of a nanoscaled composition modulated metallic glass Journal of Materials Science 49, (2014) 5640 – 5645 
13. Bachmaier A., Rathmayr G.B., Bartosik M., Apel D., Zhang Z., Pippan R. New insights on the formation of supersaturated solid solutions in the Cu–Cr system deformed by high-pressure torsion. Acta Materialia 69, (2014) 301-313
14. Hohenwarter A., Faller M., Rashkova B., Pippan R. Influence of heat treatment on the microstructural evolution of Al–3 wt.% Cu during high-pressure torsion. Philosophical Magazine Letters 94, (2014) 342-350.
15. Leitner T., Hohenwarter A., Pippan R. Fatigue crack growth behavior of ultrafine-grained nickel produced by high pressure torsion. Procedia Materials Science 3, (2014) 1044-1049 
16. Rashkova B., Faller M., Pippan R., Dehm G. Growth mechanism of Al2Cu precipitates during in situ TEM heating of a HPT deformed Al–3wt.%Cu alloy. Journal of Alloys and Compounds 600, (2014) 43-50.
17. Renk, O.; Hohenwarter, A.; Schuh, B.; Li, J. H.; Pippan, R.  Hardening by annealing: insights from different alloys. LTD, IOP PUBLISHING (Hrsg.) (36TH RISO INTERNATIONAL SYMPOSIUM ON MATERIALS SCIENCE); Riso (2015).
18. Leitner, T.; Hohenwarter, A.; Pippan, R. Revisiting fatigue crack growth in various grain size regimes of Ni.  Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process., Bd. 646[PR1] , (2015) S. 294-305. 
19. Maier, V.; Hohenwarter, A.; Pippan, R.; Kiener, D. Thermally activated deformation processes in body-centered cubic Cr - How microstructure influences strain-rate sensitivity. Scripta Mater., Bd. 106, (2015) S. 42-45. 
20. Schuh, B.; Mendez-Martin, F.; Voelker, B.; George, E. P.; Clemens, H. Pippan, R.; Hohenwarter, A.;  Mechanical properties, microstructure and thermal stability of a nanocrystalline CoCrFeMnNi high-entropy alloy after severe plastic deformation. Acta Mater., Bd. 96, (2015) S. 258-268
21. Borchers, C.; Garve, C.; Tiegel, M.; Deutges, M.; Herz, A., Edalati, K.; Pippan, R.; Horia, Z.; Kirchheim, R.;  Nanocrystalline steel obtained by mechanical alloying of iron and graphite subsequently compacted by high-pressure torsion. Acta Mater., Bd. 97, (2015)S. 207-215. Hohenwarter, A.; Pippan, R. Fracture and fracture toughness of nanopolycrystalline metals produced by severe plastic deformation.
22. Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci., Bd. 373 (2015), S. ARTN 20140366.
23. Pippan R. Hohenwarter A. The importance of fracture toughness in ultrafine and nanocrystalline bulk materials. Mater.Res.Lett. (2016) DOI 10.1080/21663831.2016.1166403