title: Properties of WZ21 (%wt) alloy processed by a powder metallurgy route.
abstract: Microstructure, mechanical properties and corrosion behaviour of WZ21 (%wt) alloy prepared by a powder metallurgy route from rapidly solidified powders have been studied. Results were compared to those of the same alloy prepared through a conventional route of casting and extrusion. The microstructure of the extruded ingot consisted of α-Mg grains and Mg3Zn3Y2 (W-phase) and LPSO-phase particles located at grain boundaries. Moreover, stacking faults were also observed within α-Mg grains. The alloy processed by the powder metallurgy route exhibited a more homogeneous and finer microstructure, with a grain size of 2 μm. In this case W-phase and Mg24Y5 phase were identified, but not the LPSO-phase. The microstructural refinement induced by the use of rapidly solidified powders strengthened the alloy at room temperature and promoted superplasticity at higher strain rates. Corrosion behaviour in PBS medium evidenced certain physical barrier effect of the almost continuous arrangements of second phases aligned along the extrusion direction in conventionally processed WZ21 alloy, with a stable tendency around 7 mm/year. On the other hand, powder metallurgy processing promoted significant pitting corrosion, inducing accelerated corrosion rate during prolonged immersion times.
authors: Department of Non-Destructive Testing, Federal Institute for Materials Research and Testing BAM, Unter den Eichen 87, 12205 Berlin, Germany; Department of Physical Metallurgy, National Center for Metallurgical Research CENIM (CSIC), Av. Gregorio del Amo 8, 28040 Madrid, Spain. Electronic address: sandra.cabeza@bam.de.
authors: Sandra
authors: S
authors: Cabeza
authors: Department of Physical Metallurgy, National Center for Metallurgical Research CENIM (CSIC), Av. Gregorio del Amo 8, 28040 Madrid, Spain.
authors: Gerardo
authors: G
authors: Garcés
authors: Department of Physical Metallurgy, National Center for Metallurgical Research CENIM (CSIC), Av. Gregorio del Amo 8, 28040 Madrid, Spain.
authors: Pablo
authors: P
authors: Pérez
authors: Department of Physical Metallurgy, National Center for Metallurgical Research CENIM (CSIC), Av. Gregorio del Amo 8, 28040 Madrid, Spain.
authors: Paloma
authors: P
authors: Adeva
mesh_terms: D000497:Alloys / Q000737:chemistry*; D003343:Corrosion; D008274:Magnesium / Q000737:chemistry; D055595:Mechanical Phenomena; D008669:Metallurgy / Q000379:methods*; D011208:Powders
chemical_list: D000497:Alloys; D011208:Powders; D008274:Magnesium
keywords: Corrosion; Creep; Magnesium; Microstructure; RE