Advanced Materials for Mechanical Engineering: Ultrafine‐Grained Alloys with Multilayer Coatings

Research has demonstrated that the formation of a bulk ultrafine‐grained (UFG) structure in metals and alloys through severe plastic deformation (SPD) enables increasing of their strength properties and decreasing of the temperature range of superplasticity. Designers and process engineers generally show a great interest in such materials because the development of mechanical engineering industries places ever‐increasing demands on the performance properties of commercial alloys, especially for parts operating under extreme conditions. One of the approaches for a comprehensive enhancement of the performance characteristics of structural materials is a combination of a UFG structure in the bulk of a material, providing an increase in strength, and an additional surface modification providing resistance to erosion and corrosion damage. As a result, a set of material service properties can be enhanced, which is difficult to achieve through only metal nanostructuring or only surface modification. This approach has been demonstrated through an example of UFG titanium alloys produced by SPD, including those with nanostructured multilayer TiVN coatings of different “architectures.” Accordingly, herein, the trends, problems, and prospects of surface modification for the innovative application of structural UFG titanium alloys in advanced mechanical engineering are examined.