Deformation behavior and acoustic emission response on uniaxial compression of extruded rectangular profile of Mg- Zn-Zr alloy

Abstract

The mechanical behavior of Mgsingle bondZnsingle bondZr alloy in a form of extruded rectangular profile is related to the initial crystallographic texture and the twinning activity. The profile with a thickness of 12 mm was uniaxially compressed in three directions (extrusion (ED), transversal (TD) and normal direction (ND)) at room temperature. Concurrently, acoustic emission (AE) measurements were performed in order to study the deformation mechanisms. The AE events, stemmed from collective dislocation movement and twin nucleation, were identified using statistical analysis of the raw AE signal. The texture evolution was studied by X-ray diffraction on samples deformed in compression up to specific stress levels. Along the ED and TD the dominant deformation mechanism is extension twinning, which is accompanied by intensive acoustic emission and strain hardening increment. In contrast, dislocation slip prevails in ND, which causes deformation curves similar to that usually observed in tension.