Magnetoplastic effect in Cu-Be alloys

Data about magnetoplastic effect (MPE) in metal alloys which arises in alloys after ageing in magnetic fields, are rather limited and controversial. At the same time the MPE in metallic alloys represents potentially a great interest from the point of view of atom-spin micromechanics and may offer a practical application in modern manufacture technologies of nanomaterials with guided properties.

A series of model Cu-Be-based alloys with different amounts of Be and Ni and the maintenance of the total amount of other magnetic impurities below 0.05 wt. % was prepared and experimentally investigated [1]: i) beryllium bronze BrB-2 (a technical alloy); ii) binary Cu-Be alloys (high purity materials, Ве amount of 0.5, 1.0, 1.6, 2.7 and 3.0 wt. %) and iii) ternary Cu-2Be-0.4Ni and Cu-2Be-1Ni alloys (in wt.%). In the present work the origin and possible mechanisms of MPE in metallic Cu-Be-based alloys are discussed. Here MPE acts as a tool for studying the type and properties of obstacles (impurity atoms, spin clusters, nano-sized precipitates of intermetallic compounds, impurity segregation at interfaces with atomic and magnetic ordering) for moving dislocations. The microstructure (determined by SEM with EBSD analysis), grain boundary segregation, fine microstructure, magnetic properties and phase composition of alloys aged in magnetic fields are reviewed.

[1] J.V. Osinskaya, A.V. Pokoev. Magneto-plastic Effect in Cu-Be Alloys with Ni Additives. Defect and Diffusion Forum 363 (2015) 186.