Effect of Rotary Swaging on Microstructure and Mechanical Properties of an AZ31 Magnesium Alloy

Abstract

The microstructure and mechanical properties of AZ31 alloy rods are investigated after rotary swaging in five successive steps. The microstructure is analyzed using light microscopy and electron backscattered diffraction. Swaged samples exhibit refined microstructure. Tensile and compression tests are conducted at room temperature. The yield stress and the ultimate stress are determined. Acoustic emission is measured in situ during straining. Deformation mechanisms are closely linked to twinning and dislocation slip in non‐basal planes.

Magnesium Reinforced with Inconel 718 Particles Prepared Ex Situ—Microstructure and Properties

“…In compression, the AE activity of twinning was close to zero above 30 MPa, which simply reflects the fact that the AE is not sensitive to twin growth. This behaviour was also observed in the textured AZ31 magnesium alloy, and the twins' growth was established by means of EBSD [18]. Hong et al, who were studying twinning in textured magnesium polycrystals deformed perpendicular to the <c> axis, estimated that various twins' variants are activated in tension and compression [27].…”

“…The acoustic emission measurements show that mechanical twinning plays an important role at the tensile (and compression) deformation of textured magnesium materials. Trojanová et al studied acoustic emission (AE) during tensile and compressive deformation of an AZ31 magnesium alloy submitted to rotary swaging [18]. They estimated massive acoustic emission at the beginning of deformation.…”

“…Newly created twins are parallel and promote the twin growth and consequently a rapid increase of the twinned volume. At a strain of 5%-6% (depending on the grain size) the whole volume is practically twinned [18]. During tension along the <c> axis, all six twin variants are possible to activate and therefore twins are formed in various directions intersecting each other.…”

Strain Hardening in an AZ31 Alloy Submitted to Rotary Swaging

“…In the previous paper [ 24 ], the acoustic emission (AE) generated during tension and compression was measured. A massive AE was observed, while deformed in tension, at the very beginning of plastic deformation.…”

“…The activities of all these parameters were studied exclusively in the cast alloys and alloys after ECAP or rolling processing. Although the texture developed in magnesium alloys during rotary swaging is often similar to the texture of extruded materials, the deformation behaviour may be different [ 24 ].…”