Recovery Mechanisms in a Compressed Ni-Ti Superelastic Alloy

AUTOR(ES)

Daer, Shimeni Baptista, Paula, Andersan, Vieira, Luiz Carlos Almeida, Teixeira, Edir Neves, Otubo, Jorge, Fernandes, Francisco Manuel Braz

FONTE

Mat. Res.

DATA DE PUBLICAÇÃO

19/10/2017

RESUMO

The present work studied the influence of annealing on a Ni-Ti alloy submitted to uniaxial compression. The stress-strain curve under compression showed the absence of the Stress-Induced-Martensite (SIM) plateau and 42% of remaining austenitic phase (B2). identified by the Electron Backscattered Diffraction (EBSD) technique on a Scanning Electronic Microscope (SEM). Annealing at 150 ºC increased the volume fraction of austenite to 70%. Annealing at 200 ºC reduced the volume fraction of austenite to 33% and increased the classical Vickers hardness and the dynamic elastoplastic hardness. This increase suggests the presence of a phase with higher indentation resistance, which can be the R phase reported in the literature. Annealing at 250 ºC decreased the classical Vickers hardness and the dynamic elastoplastic hardness, probably due to recovery. Annealing at 300 ºC advanced the recovery process and promoted some recrystallization, as suggested by the large standard deviation observed in the hardness results.

Documentos Relacionados

• The effect of residence time on the tensile properties of superelastic and thermal activated Ni-Ti orthodontic wires
• ECAE processed NiTi shape memory alloy
• Analise de falhas de instrumentos endodonticos rotatorios de Ni-Ti em odontologia
• Surface Characterization of NiTi Superelastic and Shape Memory Alloys After Electrolytic Polishing
• ToF-SIMS Characterization of Nanostructured ZrO2 Coatings Applied to Near Equiatomic Ni-Ti Alloy