Study of strengthening mechanisms in an Al-Cu-Ti metallic glass reinforced Al matrix composite consolidated by ECAP process

In this study, equal channel angular pressing (ECAP) process was used to consolidate an Al-Cu-Ti metallic glass reinforced aluminum matrix composite. The role of strengthening mechanisms in the strength of developed composite was investigated. The composite with 13 wt% of amorphous reinforcements was produced and the mechanical properties were compared with pure Al specimen which consolidated in the same conditions. Precise study of microstructural features as well as phase transformations is necessary for evaluating the role of strengthening mechanisms on mechanical properties of consolidated specimens. Hence, microstructural evolutions were examined using field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) method. Also, dislocations density was calculated through equations based on the characteristics of crystalline peaks in XRD patterns. Clemex software was also used to quantify the constituents of microstructures. The densities of the consolidated samples were measured by Archimedes method. Uniaxial compression test was utilized to determine the mechanical properties. Microstructural studies and assessment of microstructural features such as grain size and stored dislocations density revealed that strain hardening mechanism play the major role in the strengthening of consolidated specimens. On the other hand, presence of microstructural defects led to some discrepancies between measured and anticipated strength.