A focus of the current industrial sector is motivated to develop a new class of advanced materials with superior characteristics compared to currently available conventional materials. In the recent past, light metals and alloys, such as aluminum, copper, titanium, and magnesium alloys and their metal matrix composites (MMCs) have been increasingly accepted in automotive, aerospace, and biomedical sectors. Moreover, for improving the physical and mechanical characteristics of these materials, the processing of materials with secondary metalworking techniques (severe plastic deformation [SPD], complete and partial heat treatment processes, cryogenic treatment, surface coatings, etc.) is essential. Out of several secondary metalworking techniques, the most efficient is the SPD technique with equal channel angular pressing (ECAP). ECAP is widely adopted to produce materials with significantly reduced grain size and excellent properties. The current review article aims to present the effect of ECAP on the physical and mechanical characteristics of aluminum, copper, titanium, and magnesium alloys, and their MMCs are discussed. Microstructural studies and their associated statistical parameters of these materials are discussed using several destructive and nondestructive techniques. Also, the use of in-situ methods, such as digital image correlation, infrared thermography, etc., is examined to study the deformation mechanisms in ECAP. This review article provides a new direction for researchers working in materials engineering and science fields to recognize the importance of the ECAP technique on mechanical characteristics and associated microstructural changes of majorly used alloys and MMCs.

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The engineering sector researchers are always searching for new materials for their challenging applications. The aluminum alloy (AA) 357 plays a critical role in applications like automotive and aerospace because of its exceptional characteristics such as toughness, fatigue resistance, and more importantly strength-to-weight ratio, but it suffers from poor wear resistance. However, the research community is looking for enhancement in wear resistance at various loads. This research deals with AA357-Si3N4 nanocomposites fabricated through the induction stir casting method and evaluation of properties in comparison with AA357 matrix. The Si3N4 nanoparticulates were selected as reinforcement and added 0.5 to 3.0 wt.% in the steps of 0.5 wt.%. The influence of Si3N4 nano reinforcement content on hardness, strength, and wear resistance of AA357-Si3N4 nanocomposites investigative work was conducted as per ASTM standards. The studies of microstructures of AA357-Si3N4 nanocomposites were performed using an optical microscope to analyze grain structure and a scanning electron microscope (SEM) to examine particle distribution. The density, hardness, and ultimate tensile strength (UTS), in addition to morphological studies of fractured surfaces and energy dispersive spectroscopy for nanocomposites elemental study. As per ASTM G99, Standard Test Method for Wear Testing with a Pin-on-Disk Apparatus, standards, pin-on-disc equipment was used to examine tribological properties of AA357-Si3N4 nanocomposites and SEM pictures of worn nanocomposites surfaces analyzed extensively. By going through the experimental outcomes, it is realized that with increase in nano reinforcement in matrix AA357, the properties such as density, resistance to indentation/hardness, and UTS increased at the expense of percentage elongation. The pin-on-disc tribometer experimental results indicate that the fabricated AA357-Si3N4 nanocomposites have higher wear resistance.