Grain refinement of commercially pure zirconium by ECAP and subsequent intermediate heat treatment

Formation of Subsurface Zone Induced by Sliding Wear in Zirconium Studied by Positron Lifetime Spectroscopy

“…In Zr this region contains great amount of dislocations. This can be connected to the presence of shear bands and twins which were found in the microstructure of the Zr of commercial purity cold-rolled to 71 % [19] and exposed to equal channel angular pressing [20]. The values of the second lifetime component for the sample exposed to compression vary in the wide range from 250 to 420 ps indicating the presence of vacancy clusters of different sizes from monovacancy to more than nine vacancies.…”

Structurally induced enhancement in corrosion resistance of Zr–2.5%Nb alloy in saline solution by applying ultrasonic impact peening

“…2) and crystallites reorientations during first minute of treatment (ēr0.22). The formed basal texture participates essentially in the hardening process since deformation along oc4axis requires higher stresses to initiate stronger deformation modes as (10-12) tensile twinning, (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) compressive twinning and ocþa4 pyramidal slip. Precipitation strengthening of the beta grains influences on the hardness at strainsēZ0.…”

“…A number of recent studies were addressed to investigation the corrosion resistance of some Zr alloys in the conditions close to the operational ones [20]. Besides, the effects of the Nb concentration were also addressed as well as the heat treatment [21,22]. It was also pointed out that the microstructure of the surface layer predetermines the properties and structure of the oxide film formed [20,21,[23][24][25].…”

“…Besides, the effects of the Nb concentration were also addressed as well as the heat treatment [21,22]. It was also pointed out that the microstructure of the surface layer predetermines the properties and structure of the oxide film formed [20,21,[23][24][25]. The latter was shown to play an important and frequently even governing role in the overall material performance.…”

Effects of heat treatments on AA6061 aluminum alloy deformed by cross-channel extrusion

“…Several methods were designed to produce UFG materials by accumulating strains without changing the initial dimension of the material, such as equal channel angular extrusion (ECAE) (Lee et al, 2007a;Sun et al, 2000), reciprocating extrusion (Chu et al, 2001;Lee et al, 2007b), rotary-die equal channel angular pressing (RD-ECAP) (Kim et al, 2003;Ma et al, 2005), etc. Crosschannel extrusion (CCE) (Chou et al, 2008;Chou et al, 2007) is a new method which is designed to improve the process of manufacturing a bulk fine-grained material.…”