This book presents selected peer-reviewed contributions from the 2025 International Conference on “Physics and Mechanics of New Materials and Their Applications” (PHENMA 2025), Kitakyushu, Japan, September 27–30, 2025, divided into four scientific directions: processing techniques, physics, mechanics, and applications of advanced materials. This book describes a broad spectrum of advanced nanostructures, crystals, materials and composites with specific characteristics. It presents nanotechnology approaches, modern environmentally friendly techniques and physical-chemical and mechanical studies of the structure-sensitive properties of the materials and their applications. The results obtained are based on new achievements in material sciences and computational approaches, methods and algorithms (in particular, finite-element modeling) applied to the solution of different technological, mechanical and physical problems. The results obtained have a significant interest in theory, modeling and testing the advanced materials. Other results are devoted to promising devices demonstrating high accuracy, longevity and new opportunities to work effectively under critical temperatures and high pressures, in aggressive media, etc. These devices show improved comparative characteristics, caused by designed and developed materials and composites, allowing study of physical and mechanical processes and phenomena, based on scientific and technological progress.