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Fracture is the ultimate step of any kind of continued deformation process undergone in a material. If this viewpoint is correct then it will be plausible to relate the geometric fracture surface appearances with the entire deformation path/history subjected to the material previously. The two-dimensional dimple geometry quantified from the open published tensile fractographs are investigated to predict the nature of variation in corresponding deformation and fracture properties of a Zircaloy-4 with systematic swaging and swaging + annealing treatments. The changes in microstructure and texture that led to non-identical two-dimensional ductile fracture characteristics/patterns at different initial feed rate during swaging and swaging + annealing treatments have been (quantitatively) assessed, compared and correlated with the respective mechanical responses of the material. Image texture analysis has also been carried out to understand the clear variation in fracture morphologies as a function of initial feed rate for both treatments. [ABSTRACT FROM AUTHOR]

This paper discusses different techniques for making copper wire in the fourth and third centuries BCE in ancient Macedonia (Northern Greece). Wire was used to form stems on gilded wreaths, and to support berries, leaves and rosettes. Stems were made in one piece with the leaves, and are likely to have been formed in at least two ways: one involved cutting them out of sheet copper about 0.5 mm thick, which was creased and then hammered into shape; the other involves using copper rods 1mm square. Some of the square copper rods can be seen on the wreaths, and their regularity suggests they may have been formed on a swaging block. Berries were joined to the wreath circlets by round wires, formed in some cases, it is suggested, by hammering sheet metal around a central core; in other cases, these stems may have been formed by rolling a rod between stone slabs. No evidence, such as longitudinal striations, was found of drawing. Some examples of strip-twisted wire were found, but there are fewer cases of this than of wire formed by hammering. The most expensive gilded wreaths at Derveni, cist grave A, Phoinikas cist grave 5 and Sedes, sometimes had special features, such as gilded copper tubes (‘branches’) with smaller stems on either side, or square wires formed into spirals.

This paper discusses different techniques for making copper wire in the fourth and third centuries BCE in ancient Macedonia (Northern Greece). Wire was used to form stems on gilded wreaths, and to support berries, leaves and rosettes. Stems were made in one piece with the leaves, and are likely to have been formed in at least two ways: one involved cutting them out of sheet copper about 0.5 mm thick, which was creased and then hammered into shape; the other involves using copper rods 1mm square. Some of the square copper rods can be seen on the wreaths, and their regularity suggests they may have been formed on a swaging block. Berries were joined to the wreath circlets by round wires, formed in some cases, it is suggested, by hammering sheet metal around a central core; in other cases, these stems may have been formed by rolling a rod between stone slabs. No evidence, such as longitudinal striations, was found of drawing. Some examples of strip-twisted wire were found, but there are fewer cases of this than of wire formed by hammering. The most expensive gilded wreaths at Derveni, cist grave A, Phoinikas cist grave 5 and Sedes, sometimes had special features, such as gilded copper tubes ('branches') with smaller stems on either side, or square wires formed into spirals. [ABSTRACT FROM AUTHOR]

In thiswork, a 24-month two-batch fuel management strategy for the APR1400 using LEU + has been investigated, where enrichments of 5.9 and 5.2 w/o are utilized in lieu of the conventional 4–5 w/o UO2 fuel. In addition, an Accident Tolerant Fuel (ATF) clad based on the swaging technology is applied to APR1400 fuel assemblies. In this special ATF clad design, both outer and inner SS316 layers protect the conventional zircaloy clad. Erbia (Er2O3) is introduced as a burnable absorber with two-fold goals to lower the critical boron concentration in the long-cycle LEU + loaded core as well as to handle the LEU + fuel in the existing front-end fuel facilities without renewing the license. Two types of fuel assemblies with different loading of gadolinia (Gd2O3) are considered to control both the reactivity and the core radial power distribution. The erbia burnable absorber is uniformly admixed with UO2 in all fuel pins except for the gadolinia-bearing ones. In this study, two core designs were devised with different erbia loading, and core performance and safety parameters were evaluated for each case in comparison with a core design without any burnable absorbers. The core analysis was done using the two-step method. First, cross-sections are generated by the SERPENT 2 Monte Carlo code, and the 3-D neutronic analysis is performed with an in-house multi-physics nodal code KANT.

The critical study is focused on improving ductility by maintaining higher strength of swaged Zircaloy-4 through specifically optimized annealing treatment. It has led to evolution of texture to obtain stable (21¯1¯0) pyramidal type in the microstructure, enhanced elongation up to ∼20%. An excellent combination of ductility and strength was achieved through low-strain-swaging followed by annealing optimization, unlike other resource-intensive and conventional SPD techniques. Improvements in mechanical properties, especially ductility enhancement, were substantiated with the detailed and targeted microstructural analysis with EBSD and TEM.

Electron microscopy is used to study the evolution of microstructure of copper–aluminum composites, which takes place as the degree of reduction upon rotary swaging increases, and their conductivity is measured. The effect of reinforcing the copper–aluminum composites with steel fibers on the conductivity is studied. [ABSTRACT FROM AUTHOR]

In this work, three different states of Mg-9.1Y-1.8Zn alloys including as-cast, extruded and swaged were prepared by semi-continuous casting, extrusion and swaging processes, respectively. Their compositions, microstructures and hydrogen storage properties were investigated. The results show that Mg-9.1Y-1.8Zn alloys in three different states are all composed of Mg and long-period stacking ordered (LPSO) phases. The LPSO phases occurs to break and decompose after hydrogenation and in-situ forms the YH χ(χ = 2,3) nano-hydrides. The nano-hydrides can be used as in-situ catalysts to improve the hydrogen storage properties of alloys. Meanwhile, many nanocrystalline grains appear in the core of alloy after swaging, and the average grain size ranges from 80 to 200 nm. The presence of nanocrystals may increase the specific surface area of alloy, facilitating the diffusion and absorption of hydrogen. Comparatively, the swaged alloy exhibits the largest hydrogen storage capacity and excellent hydrogen sorption kinetics relative to other states of alloys. • The as-cast, extruded, and swaged Mg-9.1Y-1.8Zn alloys were prepared. • The LPSO phases decomposes and in-situ forms YH χ(χ = 2,3) hydrides upon hydrogenation. • The YH χ(χ = 2,3) hydrides present in-situ catalytic and pinning effects on Mg matrix. • The swaged alloy exhibits the highest hydrogen storage capacity. [ABSTRACT FROM AUTHOR]

The present study aimed to discover the effect of cold swaging reduction on the bulk gradient structure formation and mechanical properties of a 316-type austenitic stainless steel. The initial rod was subjected to radial swaging until 20–95% reduction of initial rod diameter, at room temperature. According to finite element simulation, higher plastic strain was accumulated in the surface layer compared to the center region during swaging. Microstructural investigations revealed three-stage gradient structure formation in the center and edge regions of the deformed rod. Meanwhile, cold swaging resulted in the development of strong 111ǁBA, 001ǁBA, and weak 111ǁBA texture components in the center and edge, respectively. Significant tensile strengthening was observed after cold swaging. For instance, the yield strength (YS) increased from 820 MPa to 930 MPa after 40–80% reduction respectively, without the loss of ductility (δ–14%). This unique aspect of the mechanical behavior was attributed to the gradient structure of the cold swaged material and explained in detail. [ABSTRACT FROM AUTHOR]