Published in Materials
Increasing the strain rate at superplastic forming is a challenging technical and economic task of aluminum forming manufacturing. New aluminum sheets exhibiting high strain rate superplasticity at strain rates above 0.01 s−1 are required. This study describes the microstructure and the superplasticity properties of a new high-strength Al-Zn-Mg-bas...
Published in Physics of Metals and Metallography
AbstractThe microstructure and acting superplastic deformation mechanisms in the high-strength Al–7.0% Zn–2.7% Mg–1.0% Ni–0.9% Fe alloy low-doped with Sc and Zr upon deformation at a temperature of 480°С and a strain rate of 1 × 10–2 s–1 at a stable flow stage in a true strain range of 1.1 to 1.6 have been investigated. To evaluate the contribution...
Metals in small volumes display a strong dependence on initial conditions, which translates into size effects and stochastic mechanical responses. In the context of crystal plasticity, this amounts to the role of pre-existing dislocation configurations that may emerge due to prior processing. Here, we study a minimal but realistic model of uniaxial...
Published in Nanomaterials
The development of metal nanocomposites reinforced by carbon nanotubes (CNTs) remains a focus of the scientific community due to the growing need to produce lightweight advanced materials with unique mechanical properties. However, for the successful production of these nanocomposites, there is a need to consolidate knowledge about how reinforcemen...
The work-hardening behavior of Cu&ndash / Ni alloys with high stacking-fault energies (SFEs) is experimentally investigated under uniaxial compression. It is found that, with the increase of Ni content (or short-range clustering, SRC), the flow stress of Cu&ndash / Ni alloys is significantly increased, which is mainly attributed to an enhanced cont...
Published in American Mineralogist
A transition from A-type to E-type fabrics in olivine may be the cause of a decrease in seismic anisotropy with depth in the upper mantle. To better understand upper mantle seismic signals, we investigate the origin of E-type fabrics using a natural olivine by deformation experiments. An olivine crystal was first hydrated at 5 GPa and 1473 K (with ...
Published in Physics of Metals and Metallography
AbstractParameters of superplasticity of the Al–7.6% Mg–0.6% Mn–0.25% Cr alloy have been studied in the range of 490–520°C, and the optimum temperature of deformation has been determined. The evolution of the grain structure in the bulk and on the surface of samples during the superplastic deformation at a temperature of 510°C has been analyzed. Th...
This research focuses on the microstructural characterization of nickel matrix composites reinforced by carbon nanotubes (CNTs). The nanocomposites were produced by a conventional powder metallurgy process and the dispersion of CNTs and mixture with nickel powders was performed in a single step by ultrasonication. Microstructural characterization o...
Published in Materials Science
We study the fatigue life of springs made of manganese steel (0.66% С and 1.02% Mn) after four modes of heat treatment leading to the formation of troostite, martensitic–bainitic, and bainitic–martensitic structures. Springs are studied under the conditions of strain-controlled cyclic loading similar to the operating conditions of products intended...
Published in Journal of Wuhan University of Technology-Mater. Sci. Ed.
The fatigue behavior of 30WGP1600 non-oriented electrical steel, which is generally used in the motors for electrical vehicles, was investigated. The detailed microstructure and dislocation configurations of the fatigue specimens were examined by OM, SEM, and TEM. The test results showed that fatigue cracks were commonly initiated from the surface ...
