Effect of pre-straining on the aging behavior and mechanical properties of an Al-Cu-Mg-Ag alloy

The effects of cold deformation prior to aging on the precipitation behavior, microstructure and mechanical properties of an Al-5.6Cu-0.72 Mg-0.5Ag-0.32Mn-0.17Sc-0.12Zr (in wt%) alloy were investigated. Pre-straining disrupts the formation of Mg–Ag co-clusters, modifying the normal precipitation sequenc

Effect of grain size on cryogenic mechanical properties of an Al-Mg-Sc alloy

An aluminum alloy with a chemical composition of Al-6%Mg-0.35%Mn-0.2%Sc- 0.08%Zr-0.07%Cr (in wt.) and an initial grain size of ~22 μm was subjected to equal-channel angular pressing (ECAP) at 593 К up to a total strain of ~12. Extensive grain refinement provided the formation of fully recrystallized structure with an average grain size of -0.6 μm. The mechanical properties of the alloy in two different structural conditions were examined at temperatures ranging from 77 to 293 K. It was shown that ECAP highly enhanced the strength, ductility and fracture toughness of the material over the wide temperature interval. Positive effect of grain refinement tends to increase with decreasing temperature due to suppression of brittle intergranular fractur

Effect of rolling on mechanical properties and fatigue behavior of an Al-Mg-Sc-Zr alloy

An aluminum alloy with a chemical composition of Al-6%Mg-0.35%Mn-0.2%Sc-0.08%Zr-0.07%Cr (in wt.) was rolled up to different reductions of 75, 88 and 95% at 360°C and at ambient temperature. The static mechanical properties and the high-cyclic fatigue (HCF) life were examined. It was shown that the hot rolling results in increased yield stress (YS) and ultimate tensile strength (UTS). However, ductility and fatigue limit of the hot rolled alloy and initial as-cast ingot are nearly the sam

Abnormal grain growth in fine-grained aluminum produced by friction-stir welding

In this work, fundamental aspects of abnormal grain growth, which typically occurs during annealing of friction-stir welded (FSW) aluminium, were studie

Strengthening mechanisms in a Zr-modified 5083 alloy deformed to high strains

The effect of extensive grain refinement through equal-channel angular processing (ECAP) at 300°C on the mechanical properties was examined in a Zr-modified 5083 aluminum alloy. It was shown that any increase in the yield stress (YS) by increasing the number of pressings was attributed to additional contributions from three strengthening mechanisms :(i) grain boundary strengthening related to the size of the crystallites bounded by deformation-induced high-angle boundaries (HAB), (ii) dislocation strengthening related to highly increased dislocation density and(iii)solute strengthening related to promoting dynamic strain aging (DSA) by intense plastic strainin

Mechanisms of dynamic recrystallization in aluminum alloys

Mechanisms of dynamic recrystallization operating at severe plastic deformation in a wide temperature range are reviewed for aluminum alloys. The main mechanism of grain refinement in all aluminum alloys is continuous dynamic recrystallization (CDRX). Temperature, deformation process and distribution of secondary phases strongly affect the CDRX mechanism. Initial formation of geometrically necessary boundaries (GNBs) and a dispersion of nanoscale particles accelerate CDRX facilitating the formation of a 3D network of low-angle boundaries (LAB) followed by their gradual transformation to high-angle boundaries (HAB

Short-range ordering and mechanical properties of a Ni-20%Cr alloy

The mechanical behavior of a coarse-grained (100 mm) nickel-base alloy nichrome (Ni-20%Cr) was studied in compression at temperatures ranging from 150 to 1000°C. It was shown that in the temperature interval of 300-600°C this alloy demonstrates the following features of mechanical behavior: i) positive temperature dependence of yield stress; ii) jerky flow associated with the Portevin-Le Chatelier (PLC) effect ; 3) very high value (115 MPa) of “threshold” stress at 650°C. These features of mechanical behavior can be related to short- range ordering (SRO). It was shown by differential scanning calorimetry that SRO takes place in this temperature range, causing PLC effect and positive temperature dependence of yield stress. In addition, SRO has persistency effect on yield stress and creep resistanceyesBelgorod State Universit

Comparative analysis of the microstructure and mechanical properties of an Al-Cu-Mg-Ag alloy peak-aged at relatively low and high temperatures

The aim of the present work is to characterize the precipitate microstructure in relationship with the peak mechanical properties of an Al-Cu-Mg-Ag alloy reached after aging at relatively low (150 °C) and high (190 °C) temperature

Effect of the strain rate on the low cycle fatigue behavior of a 10Cr-2W-Mo-3Co-NbV steel at room temperature

The effect of a strain rate varying from ̴10-3 to ̴10¯⁵ s¯¹ at a strain amplitude ranging from ±0.25% to ±0.6% on the low cycle fatigue (LCF) behavior and the microstructure of a 10%Cr-2%W0.7%Mo-3%Co-NbV steel with 0.008 wt.

Effect of short-term aging on the impact toughness of advanced 10% CR steel

Heat-resistant high-chromium martensitic steels are widely used in various critical components of fossil power plants due to their superior creep resistance and high-temperature strengt