Guide wire devices and methods for their manufacture. The guide wire devices described herein include an elongate guide wire member that includes at least one section fabricated from a nickel-titanium (Ni—Ti) alloy that exhibits an elevated plateau stress and a narrowed stress hysteresis profile (e.g., a plateau stress of about 500 MPa to about 820 MPa and a stress hysteresis width in a range from about 250 MPa to about 80 MPa). Raising the plateau stress and narrowing the stress hysteresis width of Ni—Ti used in a guide wire device can significantly improve the steerability of the guide wire device while maintaining the flexibility, durability, and kink resistance that is typical of superelastic Ni—Ti alloys.
