Stress-strain behavior of porous Ni-Ti shape memory intermetallics synthesized from powder sintering

The microstructure and stress-strain behavior of porous Ni-Ti intermetallic s fabricated by powder sintering of Ni, Ti and/or TiH2 are investigated. Th e pores are small and well distributed in the present porous Ni-Ti alloys a nd the phase constituent and stress-strain behavior of porous Ni-Ti alloys are significantly influenced by the sintering conditions (sintering tempera ture and sintering time) and TiH2 additions. With increasing sintering temp erature, the pseudoelasticity (PE) increases while the hysteretic width dec reases. A second compression also leads to an increase of PE, elastic modul us and related deformation resistance. Further, the stress-strain behavior of porous Ni-Ti alloys is different in some way from that of bulk Ni-Ti all oys and other porous materials. (C) 2000 Elsevier Science Ltd. All rights r eserved.