Effects of Nitrogen Content on the Structure and Mechanical Properties of (AlCrFeNiTi)N High-Entropy Films by Reactive Sputtering.

In this study, (AlCrFeNiTi)N high-entropy films are prepared by a reactive direct current (DC) magnetron sputtering at different N flow rates on silicon wafers. It is found that the structure of (AlCrFeNiTi)N high-entropy films is amorphous, with x = 0. It transforms from amorphous to a face-centered-cubic (FCC) structure with the increase of nitrogen content, while the bulk AlCrFeNiTi counterpart prepared by casting features a body-centered-cubic (BCC) phase structure.

Nanocrystals generated under tensile stress in metallic glasses with phase selectivity.

Revealing the mechanism of phase selectivity can provide guidance for controlling crystals with certain phases for special properties. In the present work, nanocrystals of about 2-4 nm diameters with a B2 structure (thermodynamic metastable phase) are generated from CuZr glassy fiber by applying tensile stress at ambient temperature. By combining the ab initio calculations with the molecular dynamics simulations, the stabilities of B2 austenite and B19' martensitic phases under applied tensile stress are compared, and the phase transformation mechanism is revealed.