Az31 Magnesium Alloy Extrusion Deformation And Properties

The super-light magnesium alloys are considered to be quite a strong candidate among the "conventional materials" for the next generation appliacations, due to their low weight and good recycling ability. Unfortunately, The poor room-temperature formability combining with lower tensile yield strength confined their application. In order to overcome this serious obstale, especially to improve the ductiliy of AZ31 alloys and get a higher tensile yield strength (TYS), a deeply study on plastic deformation of AZ31 alloy was taken in this paper. One of the important methods to improve the mechanical properties of products for metal structure material is plastic deformation. In this paper, equal channel angular pressing (ECAP) and traditional extrusion had been used to alter deformation conditions, and achieved a good mechanical properties at room-temperature by modifying crystalline structure of magnesium alloys including grain size and preferred orientation distribution. The relationship between microstructure, mechanical properties and deformation condition was investigated by making use of optical microscopy (OM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and tensile test at room temperature. The results indicated that: as-cast AZ31 alloys after ECAP, the ductibility and TYS improved along with grains refined, and the relationship between the TYS and the grain size satisfy Hall-Petch correlation; as-ECAPed magnesium alloys with fine grains after traditional extrusion, the ultimate tensile strength (UTS) and TYS got a higher improvement, moreover TEM andXRD analysis revealed that the improvement of TYS attributed to the varying of grain size and grain prefered orientation distribution during the extrusion.