Electron Irradiation Induced Multistage Martensitic Transformation in Ti‐Rich Ti−Ni Alloy

Abstract

This paper focuses on the microstructure and martensitic transformation of titanium−nickel (Ti−Ni) alloys under electron irradiation. There is no observable change of the microstructure after irradiation. Abnormal multistage martensitic transformations are observed in Ti‐rich Ti‐48 at % Ni alloys after electron irradiation. The three‐stage reverse martensitic transformation can be achieved in the irradiated alloy, while unirradiated counterpart displays normal one‐stage transformation during heating processes. The abnormal reverse martensitic transformation behavior caused by electron irradiation is due to the local stress field and the excessive defect concentration. The martensitic transformation behavior and temperature after annealing at 250 °C are consistent with the unirradiated counterpart. Additionally, the irradiated alloy exhibits superior thermal cycle stability to unirradiated samples.

Direct Evidence of the Dynamic Growth of Nanotwinned Copper Grain upon Electron Beam Irradiation

“…The electron beam irradiation in a high-voltage transmission electron microscope can facilitate the phase transformation for alloys or oxides that are mainly caused by the introduction of defects through radiation damage. − However, the phase transformation is unlikely taking place when subject to the electron beam irradiation under low accelerating voltage. By varying the accelerating voltage of transmission electron microscope, Zu et al investigated the effect of critical accelerating voltage of the electron beam on the phase transformation of TiNi alloy.…”