Ultra-fast amorphization of crystalline alloys by ultrasonic vibrations

Abstract

• A facile and rapid solid-state amorphization method was discovered. • The tuning of amorphous content was achieved. • Ultrasonic vibration method exhibits an outstanding time advantage than other methods. • The elements redistribute uniformly and rapidly under ultrasonic vibration. • A new order-disorder transition mechanism was introduced. The amorphization of alloys is of both broad scientific interests and engineering significance. Despite considered as an efficient strategy to regulate and even achieve record-breaking properties of metallic materials, a facile and rapid method to trigger solid-state amorphization is still being pursued. Here we report such a method to utilize ultrasonic vibration to trigger amorphization of intermetallic compound. The ultrasonic vibrations can cause tunable amorphization at room temperature and low stress (2 MPa) conveniently. Remarkably, the ultrasonic-induced amorphization could be achieved in 60 s, which is 360 times faster than the ball milling (2.16 × 10 4 s) with the similar proportion of amorphization. The elements redistribute uniformly and rapidly via the activated short-circuit diffusion. Both experimental evidences and simulations show that the amorphous phase initiates and expands at nanograin boundaries, owing to the induction of lattice instability. This work provides a groundbreaking strategy for developing novel materials with tunable structures and properties.