Nuclear energy provides more than 10% of electrical power internationally, and the increasing engagement of nuclear energy is essential to meet the rapid worldwide increase in energy demand. A paramount challenge in the development of advanced nuclear reactors is the discovery of advanced structural materials that can endure extreme environments, such as severe neutron irradiation damage at hig...

Ultrasound is widely used in the treatment of materials. Its applications melt processing, surface hardening or finishing, metal forming, welding, etc., are well known and have been reviewed numerous review articles books. Among ultrasound-assisted processes, direct action ultrasonic waves on structure properties bulk materials special interest. Ultrasonic induce oscillating shear stresses whic...

the formation of nano/ultrafine grained ferrite in low carbon steels containing different amounts of niobiumwas investigated using thermomechanical treatment which consisted of annealing of 85% cold rolled martensite with different parameters. the specimens were characterized by optical and scanning electron microscopy and vickers hardness test. a lamellar dislocation cell structure was formed ...

Materials with ultrafine-grained structure and unique physical and mechanical properties can be obtained by methods of severe plastic deformation, which include processes of asymmetric rolling (AR). Asymmetric rolling is a very effective way to create ultrafine-grained structures of metals and alloys. Since the asymmetric rolling is a continuous process, it has great potential for industrial pr...

Large-scale production of high purity (99.999%), nano-twinned, and ultrafine-grained copper foils (22 m thick) was successfully implemented by the use of nanoscale multilayer technology. The process allows the production of up to fourteen 10 cm diameter foils during a single deposition run with high levels of reproducibility. Mechanical tests demonstrate that the strength of the Cu foils (σy ∼ ...

Abstract Copper rods with ultrafine-grained microstructure, obtained by multi-turn ECAP processing, were subjected to Direct Drive Rotary Friction Welding using various processing parameters, such as rotational speed and pressure, which resulted in different energy heat input. Even though friction welding is a high process, proper selection of parameters it was possible maintain grain size at a...

Ultrafine-grained pure titanium prepared by equal-channel angular pressing has favorable mechanical performance and does not contain alloy elements that are toxic to the human body. It has potential clinical value in applications such as cardiac valve prostheses, vascular stents, and hip prostheses. To overcome the material's inherent thrombogenicity, surface-coating modification is a crucial p...

1 List of symbols and abbreviations 3 Chapter 1: INTRODUCTION 6 Chapter 2: LITERATURE SURVEY 8 2.1: The essence of ultra fine grained materials 8 2.2: Severe plastic deformation: a method for producing UFG microstructure 11 2.3: Physical properties of materials derived from GB character 15 2.4: Non-equilibrium GBs: theoretical aspects 16 2.4.1: Conventional models for GB structure 16 2.4.2: Mod...

Bauschinger test in uniaxial tension-compression mode was carried out for the first time on pure Al specimens having homogeneous ultra-fine grained (UFG) microstructures fabricated by equal-channel angular pressing (ECAP) and subsequent annealing processes. Significant stress (transient softening), energy parameter their strong dependences tensile plastic pre-strain at very early stage of defor...

In the Ultra-steel project at the National Institute for Materials Science (NIMS), which run from 1996 to 2005, high-Si-Al-content ultrafine-grained (UFG) weathering steel was developed by grain refinement and weathering guidance. It was found that this steel has excellent strength, toughness and corrosion resistance. Samples were prepared by multi pass warm rolling at temperatures between 773 ...