Evolution of Microstructure, Texture and Mechanical Properties of ECAP-Processed ZK60 Magnesium Alloy

In this work, the influence of equal channel angular pressing (ECAP) on the microstructure, texture, and mechanical properties of ZK60 Mg alloy was investigated. The deformation process by equal channel angular pressing has been performed at the three temperatures of 588, 628, and 668 K and different ECAP pass numbers up to 4. The microstructural evolution was investigated using an optical microscope (OM), scanning electron microscope (SEM) equipped with an EDS detector, and X-ray diffraction (XRD) analyses. After the ECAP process, the microstructure of the cast alloy with an average grain size of about 208 μm converted to the bimodal grain structure. The fractions of fine grains increase and their size decreases with the increasing ECAP pass number and the decreasing deformation processing temperature. The results show that the ECAP process improves the mechanical properties at room temperature and weakens them at high temperatures. In addition, enhancement of the deformation severity through increasing the number of ECAP passes and decreasing the ECAP temperature led to an increase in the hardness of the alloy at room temperature and a decrease in its creep resistance at high temperatures.

Graphical Abstract