title: Magnetic properties of single crystalline expanded austenite obtained by plasma nitriding of austenitic stainless steel single crystals.
abstract: Ferromagnetic single crystalline [100], [110], and [111]-oriented expanded austenite is obtained by plasma nitriding of paramagnetic 316L austenitic stainless steel single crystals at either 300 or 400 °C. After nitriding at 400 °C, the [100] direction appears to constitute the magnetic easy axis due to the interplay between a large lattice expansion and the expected decomposition of the expanded austenite, which results in Fe- and Ni-enriched areas. However, a complex combination of uniaxial (i.e., twofold) and biaxial (i.e., fourfold) in-plane magnetic anisotropies is encountered. It is suggested that the former is related to residual stress-induced effects while the latter is associated to the in-plane projections of the cubic lattice symmetry. Increasing the processing temperature strengthens the biaxial in-plane anisotropy in detriment of the uniaxial contribution, in agreement with a more homogeneous structure of expanded austenite with lower residual stresses. In contrast to polycrystalline expanded austenite, single crystalline expanded austenite exhibits its magnetic easy axes along basic directions.
authors.affiliation: Instituut voor Kern- en Stralingsfysica, KU Leuven , Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
authors.forename: Enric
authors.initials: E
authors.lastname: Menéndez
authors.forename: Claude
authors.initials: C
authors.lastname: Templier
authors.forename: Pablo
authors.initials: P
authors.lastname: Garcia-Ramirez
authors.forename: José
authors.initials: J
authors.lastname: Santiso
authors.forename: André
authors.initials: A
authors.lastname: Vantomme
authors.forename: Kristiaan
authors.initials: K
authors.lastname: Temst
authors.forename: Josep
authors.initials: J
authors.lastname: Nogués