论文部分内容阅读
By applying tensile stress along 〈100〉 of β phase, the superelastic behavior and stabilization of stress induced martensite (SIM) of Cu 13.4Al 4.0Ni(mass fraction, %) single crystals were studied. The results show that the pseudo yield stress decreases with the increase of cycling number, and keeping load isothermally has an effect on stabilization of SIM. Previous thermal cycling between ( M s-20 ℃) and ( A f+20 ℃) promotes the superelasticity and the stabilization of SIM as well; the pre thermal cycling also reduces the pseudo yield stress. However, once the stabilization of SIM is produced, it can be destabilized by either the afterwards thermal cooling heating cycling or load and immediately unload cycling in ( A f～ M d). Isothermal treatment in ( A f～ M d) brings restabilization of SIM. The maximum superelastic value from β → β ′ 1(18 R ) is 9% for the studied single crystal. When test temperature is in A f～( A f+50 ℃) and stress is in 0～350 MPa, the superelastic behavior exist. [
The results show that the pseudo-yielding of martensite (SIM) of Cu 13.4Al 4.0Ni (mass fraction,%) single crystals were studied. The results show that the pseudo-yielding of the β phase, the superelastic behavior and stabilization of stress induced martensite with the increase of cycling number, and keeping load isothermally has an effect on stabilization of SIM. Previous thermal cycling between (M s-20 ° C) and (A f + 20 ° C) promotes the superelasticity and the stabilization of SIM as well; the pre thermal cycling also reduces the pseudo yield stress. However, once the stabilization of SIM is produced, it can be destabilized by either the afterwards thermal cooling heating cycling or load and immediately unload cycling in (A f ~ M d). Isothermal treatment in (A f ~ M d) brings restabilization of SIM. The maximum supelastic value from β → β ’1 (18 R) is 9% for the studied single crystal. When test temperature is in A f ~ A f + 50 ° C) and stress is in 0 ~ 350 MPa, the superelastic behavior exist. [