applied sciences  
_Editorial_ Special Issue on Metal-Based Composite Materials: Preparation, Structure, Properties and Applications  
1 _Laboratory of the Electrochemical Devices and Materials, Ural Federal University, Mira St. 28, 620002 Yekaterinburg, Russia; [PERSON]_[EMAIL_ADDRESS]  
The Special Issue is aimed at analyzing modern trends and recent advances in the synthesis of new metal-based composite materials. Such composites are increasingly used in civil, automotive, and aerospace engineering, shipbuilding, robotics, nuclear power, portable energy devices, biomedicine, electronic devices, and portable aircrafts. Non-ferrous metals are often used as the matrix of composites, aluminum, magnesium, nickel, titanium and their alloys, and can act as modifiers with boron, carbon structures, borides, carbides, nitrides, and oxides of refractory metals and high-strength steel. For high-temperature composites, tungsten or molybdenum fibers are used. Despite the large number of scientific works in this area, new methods for the synthesis of such composites in order to improve and optimize their structure and properties are still needed. In this regard, experimental and theoretical works aimed at developing and optimizing methods for the synthesis of composite materials, as well as the search for new materials, have been successfully published in this Special Issue. Thirteen papers devoted to the development of composite materials for different applications are published in this Special Issue [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]. Among them, the main scientific topics include the following:  
* Light metals (Al)-based materials and alloys (Al-Mg, Al-Mg-Zn) [1, 2, 3, 8, 9, 13] with modifying and reinforced additions (Fe [2], SiC [3, 13], Al\({}_{2}\)O\({}_{3}\)[8]) used as structural materials and coatings [9], as well as the steel-filament-reinforced carbon fiber for general use [6];
* Silicon-containing materials for lithium-ion batteries with increased specific capacity [4, 12];
* Oxide materials for modern energetic devices [7, 11];
* Multi-layer structures based on graphene for the synthesis of semiconductive materials [10];
* Materials for catalysis [5]. The applicability of these developed materials goes far beyond the declared topics of the Special Issue. Here, we provide a brief description of the published papers. The authors of work [1], using a molecular dynamics method, aim to investigate the details of the fabrication techniques of an Al-Mg composite with improved mechanical properties. It is shown that shear strain has a crucial role in the mixture process. According to the tensile tests, a fracture occurred in the Mg part of the final composite sample, which means that the interlayer region, where the mixing of Mg and Al atoms is observed, is much stronger than the pure Mg part. The aim of work [2] is to investigate the microstructural and mechanical properties of a nanostructured Al-based matrix reinforced with Fe40 Al intermetallic particles. The results indicate that the hardness varies linearly with the increase in the concentration of the Fe40 Al intermetallic phase present in the composite material, and it grows almost linearly with the rising dislocation density and with the reduction in the grain size. Paper [3] shows the applicability of data on the evolution of the elastic modulus measured by the instrumented microindentation technique to determine the accumulated damage in metal matrix composites under high temperature deformation. A composite material with the 7075 aluminum alloy matrix and SiC reinforcing particles is studied here. The results show that at the deformation temperature of 500 \({}^{\circ}\)C, the plastic properties of the material are significantly lower than at 300 and 400 \({}^{\circ}\)C.  
The work [4] takes into consideration the questions regarding the electrolytic production of nanosized silicon from low-fluoride molten salts. The obtained silicon deposits are used to fabricate a composite Si/C anode for a lithium-ion battery.