The improved mechanical, thermal, biological, and tribological qualities of new alloys and metal matrix composites (MMC) are displacing older steels and alloys in the sectors of aerospace and automobile engineering, as well as in biomedical science. Alloys and MMCs, have a lower density and better performance than traditional materials. There are a variety of processes used to cast MMCs, and these procedures have a significant impact on the material's properties. Additionally, the creation and reuse of recyclable materials for the development of new materials are being addressed in light of the growing demand for sustainable manufacturing.

There are still many unanswered questions in metal matrix fabrication, including the importance of the working environment for new devices, the types of matrix and reinforcing methods needed, and improvements in the processing and post-processing method. The relationship between characteristics, ingredients, and production method is critical for the development of biocompatible alloys and metal matrix nanocomposites. Aside from their inherent qualities, several alloys and composite materials have a tendency to reject machined tools, which results in premature tool failure. This is further hampered by the use of high-strength alloy, anisotropic composite construction, and high abrasion of reinforcing components. It is necessary to provide an overview of the various challenges related to the conventional and unconventional machining of the most common alloys and composite materials.

This Special Issue focuses on alloy and MMC fabrication, surface modification, and machining, as well as the improvement of microstructure and characteristics once these techniques are applied. Original research and review articles on the fabrication of metal-ceramic composites, as well as the reduction of wastes and manufacturing costs, are encouraged. Articles discussing outcomes of casting tests, as well as traditional and unique machining processes for various alloys and MMCs, are also welcome.

Potential topics include but are not limited to the following:

• Polymer matrix composites
• Green composites
• Natural fibre-reinforced composites
• Ceramic matrix composites
• Hybrid composites
• Nanocomposites
• Welding of composite materials
• Metal matrix composites
• Surface coating of lightweight materials
• Surface treatment and modification of composites
• Bio-composites
• Parametric optimization in tribology and machinability of composites
• Additive manufacturing of composites
• Nano-filler reinforced composite
• Bio-fibre extraction and processing
• Secondary or post-processing of composites