Martensite-to-martensite transformations in Cu&.sbnd;Zn alloys

摘要: Abstract Single crystal specimens of β′ CuZn alloys deformed above M s eventually transform into a single variant stress-induced martensite (SIM). Specimens cooled to f initially exhibit domains four variants, each which becomes region upon loading. In both cases (above and below ), additional loading causes the onset “advanced deformation”—the formation “pink” bands in regions SIM thermal martensite. These are identified as martensitic phase, α , is stress induced reversible on unloading. The associated with second plateau stress-strain curves crystals loaded . This double pseudoelastic phenomenon gives rise strains up 17%, completely recoverable. some instances does not reverse unloading, internal markings appear elastic twins that load cycling. Mechanical properties crystals, crystallographic analysis reported discussed. A mechanism for transformation from 9R or proposed. Also, stress-temperature phase diagram has been determined, triple point β′, SIM, suggested.