Related papers: Atomistic study of hardening mechanism in Al-Cu na…
In the present study, molecular dynamics (MD) simulations have been performed to understand the effect of nanowire size, temperature and strain rate on the variations in dislocation density and deformation mechanisms in $<$100$>$ Cu…
Nanocrystalline metals, i.e. metals with grain sizes from 5 to 50 nm, display technologically interesting properties, such as dramatically increased hardness, increasing with decreasing grain size. Due to the small grain size, direct…
Aluminum-Copper (Al-Cu) alloys are essential materials for weight reduction critical structures in the aerospace and automotive industries, yet achieving their maximum ultrahigh-strength potential remains limited by nanoscale defect control…
Nanocrystalline metals, i.e. metals in which the grain size is in the nanometer range, have a range of technologically interesting properties including increased hardness and yield strength. We present atomic-scale simulations of the…
The interaction of crystalline defects leads to strain hardening in bulk metals. Metals with high stacking fault energy (SFE), such as aluminum, tend to have low strain hardening rates due to an inability to form stacking faults and…
Achieving a combination of high mechanical strength and high electrical conductivity in low-weight Al alloys requires a full understanding of the relationships between nanoscaled features and physical properties. Grain boundary…
The mechanical properties of Cu/Nb metallic nanolaminates with different layer thickness (7, 16, 34 and 63 nm) were studied by means of micropillar compression tests from room temperature to 400 C. Both strain-rate jump and constant strain…
Molecular dynamics simulations were used to quantify mechanically-induced structural evolution in nanocrystalline Al with an average grain size of 5 nm. A polycrystalline sample was cyclically strained at different temperatures, while a…
Nanocrystalline metals with average grain sizes of only a few nanometers have recently been observed to fail through the formation of shear bands. Here, we investigate this phenomenon in nanocrystalline Ni which has had its grain structure…
Size plays an important role on the deformation mechanism of nanopillars. With decreasing size, many FCC nanopillars exhibit dislocation starvation state which is responsible for their high strength. However, many details about the…
A Cu-Cr composite was processed by severe plastic deformation to investigate the role of interphase boundaries on the grain size reduction mechanisms. The as-deformed material exhibits a grain size of only 20nm. This gives rise to a…
A complex study of aging kinetics for both coarse-grained and nanostructured by severe plastic deformation Cu -- 2 wt% Be alloy is reported. It is shown that aging of a coarse-grained alloy leads to continuous formation of nanosized CuBe…
The future of space exploration and human settlement beyond Earth hinges on a deeper understanding of in space manufacturing processes. The unique physical conditions and scarcity of experimental data demand robust computational models to…
Molecular dynamics simulations are used to investigate strain localization in a model nanocrystalline metal. The atomic mechanisms of such catastrophic failure are first studied for two grain sizes of interest. Detailed analysis shows that…
The thermal decomposition behavior, the microstructural evolution and its influence on the mechanical properties of a supersaturated Cu Co solid solution with ~100 nm average grain size prepared by severe plastic deformation is investigated…
We discuss how simulations of mechanical properties of materials require descriptions at many different length scales --- from the nanoscale where an atomic description is appropriate, through a mesoscale where dislocation based…
The effect of grain size on the flow strength of FCC polycrystals was analyzed by means of computational homogenization. The mechanical behavior of each grain was dictated by a dislocation-based crystal plasticity model in the context of…
Grain boundary complexions have been observed to affect the mechanical behavior of nanocrystalline metals, improving both strength and ductility. While an explanation for the improved ductility exists, the observed effect on strength…
Hybrid Monte Carlo (MC)/molecular dynamics (MD) simulations are conducted to study the microstructures of nanocrystalline (nc) Cu/Ag alloys with various Ag concentrations. When the Ag concentration is below 50 Ag atoms/nm!, an increase in…
The mechanical behavior of nanotwinned Cu was studied through indentation creep and constant strain rate indentation tests from 25 $^\circ$C to 200 $^\circ$C. The results showed an enhanced strain rate sensitivity of nanotwinned Cu with…