Microstructural characterization and amorphous phase formation in Co40Fe22Ta8B30 powders produced by mechanical alloying

Microstructural characterization of medical-grade stainless steel powders prepared by mechanical alloying and subsequent annealing

“…Consequently, the trickling down of mobile dislocations on the fixed dislocations contributes to the nucleation of new boundaries and a severe grain refinement. A similar contribution to structural refinement has been attributed to the interstitial dissolution of boron in mechanically alloyed cobalt-based powders [18].…”

Influence of annealing on microstructure and magnetic properties of cobalt-based amorphous/nanocrystalline powders synthesized by mechanical alloying

“…Fig. 2 reveals that the amount of amorphous phase is not notably changed after 180 h milling and its fraction reaches a maximum value of 96 wt.% after 200 h milling according to the quantitative XRD analysis [18]. Formation of the broad exothermic event before crystallization implies that the enthalpy of the milled powders decreases during the heating.…”

Development of a nanostructured Zr3Co intermetallic getter powder with enhanced pumping characteristics

“…During the MA process, the powder particles of Zr and Co are trapped between colliding balls and undergone severe plastic deformation. This process involves mass transfer between elemental powders, and is associated with the compositional changes of powder particles [28,31]. Powder particles are successively flattened, cold welded, fractured and rewelded according to the following steps [28,31]: a) cold welding and fracturing of the particles which result in mixing of Zr and Co, and the formation of intermetallic compound (see SEM macrograph in Fig.…”

“…This process involves mass transfer between elemental powders, and is associated with the compositional changes of powder particles [28,31]. Powder particles are successively flattened, cold welded, fractured and rewelded according to the following steps [28,31]: a) cold welding and fracturing of the particles which result in mixing of Zr and Co, and the formation of intermetallic compound (see SEM macrograph in Fig. 6), b) extensive formation of lattice defects, dislocations in particular, as a result of the severe plastic deformation, c) material transfer through the diffusion of Zr and Co. During ball milling, diffusion is accelerated by the lattice defects and by a localized and momentary increase in the temperature of the particles trapped between the colliding balls.…”