a nano/ultra-fine grain al-0.2wt% zr alloy was produced by accumulated roll bonding (arb) processafter 10 cycles. the fraction of high angle grain boundaries increased from 8% to 65.4% during 10passes during arb process. this alloy was subjected to tensile test at different temperatures (523,573and 623 k) and strain rates (0.1 and 0.01 s-1). the optimum condition of temperature and strain rate ...

aisi 304l austenitic stainless steel with different grain sizes of 0.5 -12 μm was obtained through the martensiticprocess. corrosion behavior of different samples was investigated in a 0.5m hcl solution using open circuitpotential, potentiodynamic polarization and electrochemical impedance spectroscopy tests. also, the correlationbetween the grain size and pitting corrosion resistance was asses...

Much attention has been directed recently to ultra-grain refining of metallic materials, where the grain size is reduced to less than 1 mm. It is expected that submicrometer grained structure would result in high strength and toughness at ambient temperature [1] as well as high strain rate or low temperature superplasticity at elevated temperatures [2,3]. It has been reported recently that ultr...

We performed molecular dynamics (MD) simulations to investigate the mechanical properties of polycrystalline graphene. By constructing molecular models of ultra-fine-grained graphene structures, we studied the effect of different grain sizes of 1-10 nm on the mechanical response of graphene. We found that the elastic modulus and tensile strength of polycrystalline graphene decrease with decreas...

Abstract: Equal channel angular extrusion (ECAE) is a promising technique for production of ultra fine-grain (UFG) materials of few hundred nanometers size. In this research, the grain refinement of aluminium strip is accelerated by sandwiching it between two copper strips and then subjecting the three strips to ECAE process simultaneously. The loosely packed copper-aluminium-copper laminated b...

Abstract: In the present investigation, the effects of thermomechanical processing parameters and the steel chemical composition on the ultra fine ferrite formation characteristics were studied. This was programmed relying on the capabilities of strain induced transformation (SIT) phenomenon and applying to different grades of Si-Mn TRIP (Transformation Induced Plasticity) steels. According...

We developed a multiscale approach to explore the effective thermal conductivity of polycrystalline graphene sheets. By performing equilibrium molecular dynamics (EMD) simulations, the grain size effect on the thermal conductivity of ultra-fine grained polycrystalline graphene sheets is investigated. Our results reveal that the ultra-fine grained graphene structures have thermal conductivity on...