Tungsten has been chosen as the main candidate for plasma facing components (PFCs) due to its superior properties under extreme operating conditions in future nuclear fusion reactors such as ITER. One of the serious issues for PFCs is the high heat load during transient events such as ELMs and disruption in the reactor. Recrystallization and grain size growth in PFC materials caused by transien...

Accumulative roll-bonding (ARB) is a severe plastic deformation process that is using rolling to produce ultrafine grains in coarse grained metallic materials. In this study, ARB has been applied on 70/30 brass up to 6 cycles at ambient temperature and non-lubricated conditions to apply a true strain up to 4.8 Von Mises strain. Microstructures of ARBed brass samples were characterized by scanni...

An ultrafine grain surface layer with average crystallite size of 28 nm was produced on annealed mild steel through a wire brushing process. The effects of grain size reduction on the inhibition performance of sodium phosphate were investigated using polarization and electrochemical impedance spectroscopy (EIS) measurements. The crystal grain size of wire brushed surface was analyzed by X-ray d...

Nanocrystalline metals are polycrystalline metals with grain sizes in the nanometer range. They have attracted significant interest in recent years due to their unique mechanical and electrical properties. The main objective of this thesis is to develop continuum-scale descriptions of nanoscale deformation and failure mechanisms in nanocrystalline metals. The research has focused on three speci...

In many cases, due to high surface stress, stress concentration and wear, the metal material starts fail from surface. It is necessary investigate interface evolution characteristics under high-speed collisions for widely used materials. The microstructures strengthening mechanism of Ni balls after with 316 L stainless steel were investigated by a self-designed test system. was found that ultra...

To investigate the effect of grain sizes on hydrogen embrittlement 4N-purity iron, miniature tensile tests were conducted after charging for ultrafine-grained specimens produced by high-pressure torsion and subsequent annealing. Hydrogen indexes defined from reduction area increased with decreasing size, shear-type fracture occurred fine dimples surface diagonally raptured specimen a smaller si...