TY - JOUR A1 - Bettge, Dirk A1 - Österle, Werner T1 - “Cube slip” in near-[111] oriented specimens of a single-crystal nickel-base superalloy JF - Scripta Materialia N2 - In the past few years, it has been discussed with increasing frequency, whether cube slip does occur in gamma' hardened nickel-base superalloys. Occurrence of cube slip has consequences for the modeling of orientation dependence of the CRSS. Until now, there are only few experimental investigations. In principle, cube slip should be possible in primitive cubic lattices (e.g. L12 ordered gamma' phase) but not in face centered cubic ones (e.g. Ni solid solution). The most favourable specimen orientations are near [111], where the Schmid factors for this type of glide exceed those for octahedral systems. There are two basic methods to detect cube slip: macroscopic slip trace analysis and Transmission electron microscopy (TEM) investigation of the dislocation structure. Few observations of cube slip by macroscopic slip traces are reported in the literature. But it is still uncertain under which test conditions cube slip occurs and what the dislocation mechanisms are. Cube slip was observed during tensile or compression tests of several first generation superalloys, but it seems not to occur during shear creep deformation (e.g. CMSX-4 at 980°C), and it is also lacking under conventional tensile or compression loading, if the gmma' particles are small. No observations were ever reported of dislocations gliding on {001} planes in matrix channels. KW - Cube slip KW - Nickel-base superalloy KW - Dislocations KW - TEM PY - 1999 DO - https://doi.org/10.1016/S1359-6462(98)00446-1 SN - 1359-6462 VL - 40 IS - 4 SP - 389 EP - 395 PB - Elsevier AN - OPUS4-38220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dörfel, Ilona A1 - Österle, Werner A1 - Urban, Ingrid A1 - Bouzy, E. T1 - Microstructural characterization of binary and ternary hard coating systems for wear protection - Part I: PVD coatings JF - Surface and coatings technology N2 - Different wear-resistant coatings produced by physical vapour deposition (PVD) were characterized with the aid of cross-sectional transmission electron microscopy (XTEM). All coating systems were optimized by the producers and exhibited good properties with respect to their special applications. The microstructure, texture and chemical composition of binary and ternary systems produced by the arc process [TiN, CrN, Cr2N (Ti, Cr)N on steel substrates] and magnetron sputtering process [TiN, CrN on steel substrates, (Ti, Al)N on Si-substrate] were investigated. All coatings had a more or less columnar microstructure, which was interrupted by interlayers in some cases. Whereas arc coatings always did show some kind of substrate modification, the latter was not observed after magnetron sputtering. Electron diffraction normally revealed a mono-phase fcc structure, except at sites very near to the interface. Only for the systems Cr–N and (Ti, Cr)–N were different additional phases observed at low nitrogen partial pressures. KW - Arc bond sputtering KW - Arc deposition KW - Magnetron sputtering KW - TEM KW - XTEM PY - 1999 UR - http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TVV-3VTRSCY-G&_user=963821&_coverDate=01%2F29%2F1999&_rdoc=14&_fmt=summary&_orig=browse&_srch=doc-info(%23toc%235544%231999%23998889997%2360972%23FLA%23display%23Volume)&_cdi=5544&_sort=d&_docanch DO - https://doi.org/10.1016/S0257-8972(98)00735-X SN - 0257-8972 VL - 111 IS - 2-3 SP - 199 EP - 209 PB - Elsevier Science CY - Lausanne AN - OPUS4-2364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -