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Using the PIT method, multifilament wire with different packing strategies has been manufactured. In all, three types of wire have been investigated, a 19-filament configuration using ex-situ powder in an Fe-matrix and two 8-filament configurations in an Fe-matrix applying a copper core, one using in-situ and another using ex-situ powder. The effect on the annealing requirements during mechanical processing of adding such a copper core has been investigated. The results show that the number of required annealings drops by about a factor of one half with the addition of a copper core. This finding is supported by numerical simulations of the deformation process which indicate that tensile stresses are concentrated around the middle of the wire during the drawing process. As such, strategic packing of the multifilament configuration can reduce the need for annealing during the mechanical deformation process. It is also found that the multifilament configuration using in-situ powder requires less annealing than the ex-situ counterpart. This is most likely due to the fact that in-situ powder is more readily compacted than ex-situ powder. [ABSTRACT FROM AUTHOR]

Abstract: The special contact conditions in skin-pass rolling of steel strip is analysed by studying plane strain upsetting of thin sheet with low reduction applying long narrow tools and dry friction conditions. An extended sticking region is estimated by an elasto-plastic FEM analysis of the plane strain upsetting. This sticking region causes a highly inhomogeneous elasto-plastic deformation with large influence of work-hardening and friction. A numerical analysis of skin-pass rolling shows the same contact conditions, i.e. an extended sticking region around the center of the contact zone. The calculated size of the sticking region with varying contact length and pressure/reduction is experimentally verified by plane strain upsetting tests measuring the local surface deformation of the work pieces after unloading. [Copyright &y& Elsevier]

Mitochondrial DNA diversity was analysed in 19 Iberian and six foreign sheep breeds. Three mtDNA lineages (B, A and C) were found in the Iberian sheep, with type B clearly predominating over the others. The results were analysed for each of the morphologically determined breed groups in Iberian sheep: Merino, Entrefino, Churro and Iberian trunks. MtDNA lineage C was found only in the Iberian trunk composed of Montesina and Ojalada. These two populations had high mtDNA variability, and in the Iberian sheep only Merino Branco had more variation. The other three Merino types studied showed moderate variability, including the most authentic Merino, the Spanish Merino. These three Merinos clustered closely in a multidimensional scaling representation of distances, while the fourth breed (Merino Branco) showed a clear separation. As for the other two trunks, breeds from the Churro group showed greater maternal uniformity while results for populations included in the so-called Entrefino trunk seemed to have a more heterogeneous maternal origin. The results obtained are discussed with available data from nuclear markers and with morphological classifications, and all this information is analysed in relation to the origin of the different Iberian sheep breeds.? [ABSTRACT FROM AUTHOR]

Abstract: To analyze the local deformation in skinpass rolling of steel strip the process was considered as a metal forming process under high friction, small reduction and with a long contact length. An elasto-plastic FEM analysis of a plane strain upsetting between plane parallel tools at small reduction was carried out. The results point out that an extended sticking region appears with a characteristic contact stress distribution, resulting in highly inhomogeneous deformation. The large influence of work hardening and high friction on the deformation pattern is shown. [Copyright &y& Elsevier]

Abstract: A new test for measurement of the mechanical properties of granular powders is proposed, consisting of upsetting the powder inside a metal tube. Varying the tube material as well as its wall thickness allows superimposing of a variable radial pressure. By pre-compacting the powder inside the tube in a closed die it is possible to test the powder at different densities. The radial pressure is found by correlating measurements of radial bulging of the tube with numerical analysis of tube bulging. Estimates of the error on the determination of the radial pressure are given and it is found that this error may be kept less than ±4%. The coefficient of friction between powder and tube for a specific case is evaluated and found to be between 0.05 and 0.1 at p c >400 MPa. Data from the test with axial pressures up to 1100 MPa and radial pressures up to 500 MPa are presented. Data on the yield surface for BSCCO (ceramic powder (Bi,Pb)2Sr2Ca2Cu3Ox for manufacturing of superconductors) at 74% density are given and found to be in good agreement with previously published data determined by closed die compaction and fracture tests. The results obtained show that the new test may be a good alternative when high pressures are required or when pressurizing by fluid is impractical. [Copyright &y& Elsevier]

The paper gives an overview of research at the authors’ department on the manufacturing of superconductors, especially Ag/BSCCO tape produced by the oxide-powder-in-tube method (OPIT). Studies include experimental optimisation of the drawing of single-filament wire as well as multi-filament wire introducing new stacking strategies in the multi-filament design, and optimisation of the flat rolling procedure adopting experimental as well as numerical methods. [Copyright &y& Elsevier]

Evaluates a three-dimensional numerical model of rolling of superconducting Ag/BSCCO superconducting tape. Relative powder density measurements; Geometry of flat rolled tape; Relation between tape thickness and tape width.

Soursop (Annona muricata L.) fruit tea is a health‐beneficial product that promotes economic development and addresses the issue of excessive agricultural waste. Prolonging the shelf‐life of soursop fruit tea has been of scientific interest currently. This study evaluated the effects of three types of packaging materials of soursop fruit tea (e.g., paper, paper‐combined Polyetylen (PE), and aluminum‐combined PE) and different storage temperatures (5, 15, 30, and 45°C) on various product characteristics, total polyphenol content (TPC), total flavonoid content (TFC), total ascorbic acid (TAA), and 2,2‐diphenyl‐1‐picryl hydrazyl (DPPH)/2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) free radical scavenging capacity during 4 weeks of storage. The results revealed that the sample stored in aluminum‐combined PE packaging at 30°C retained most of the product's characteristics and nutritional values. This was evidenced by the moisture content of 2.49%, TAA of 3.9 ± 1.4 mg/100 g dry weight, TPC of 12.89 ± 0.47 mgGAE/g, TFC of 0.54 ± 0.004 mgQE/g, DPPH scavenging activity of 4.06 ± 0.02 mgAA/g, and ABTS scavenging activity of 13.34 ± 0.32 mgAA/g. Additionally, the microbiological quality of the sample met the standard of TCVN 9740:2013. Overall, the study highlights the importance of packaging materials and storage temperatures to maintain the nutritional quality of soursop fruit tea. It provides valuable insights into the suitable storage conditions for preserving the quality and health‐promoting effects of this product. [ABSTRACT FROM AUTHOR]

This manuscript presents a combined numerical and experimental methodology for determining the stress-strain curve of metallic materials from the measurements of force and displacement obtained in the axial compression of cylindrical test specimens with friction between the specimens and the platens. The methodology is based on minimizing the error between the average surface pressure obtained from the experimental measurements of the force and displacement and that obtained from the slab method of analysis of metal plasticity. Three different friction models based on Coulomb friction, the constant friction model or combined friction models are utilized. Experimental results obtained from cylindrical and Rastegaev test specimens with different lubricants combined with the experimental determination of friction by means of ring compression tests allows compensating the effect of friction in the determination of the material flow curve. Comparison with the flow curves determined without friction compensation shows the viability of the proposed methodology. The proposed methodology is a simple and effective alternative to other solutions available in the literature and the pseudo-code supplied in the Appendix is provided for those readers interested in utilizing the associated numerical algorithm for determining the stress-strain curves of metallic materials. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present investigation was to examine the possibility of reducing lubrication and replacing expensive tungsten carbide material in blanking/piercing through introduction of hard tool coatings. Results show that hard PVD coatings can be successfully used in blanking/piercing applications, even on softer tool steels, thus leading to reduced friction and wear as well as to lower costs of the tool. However, preparation of the substrate material and good coating to substrate adhesion are crucial. On the other hand, even with the use of low friction coating (DLC) stamping force exceeds critical value under dry friction conditions and leads to tool failure. Therefore, at present oxidation and temperature resistant hard coatings can give improved wear resistance of stamping tools, but elimination of lubricants in blanking and piercing processes is still not feasible. [Copyright &y& Elsevier]

Weldability of a new lightweight sandwich material, LITECOR®, by resistance spot welding is analyzed by experiments and numerical simulations. The spot welding process is accommodated by a first pulse squeezing out the non-conductive polymer core of the sandwich material locally to allow metal-metal contact. This is facilitated by the use of a shunt tool and is followed by a second pulse for the actual spot welding and nugget formation. A weldability lobe in the time-current space of the second pulse reveals a process window of acceptable size for automotive assembly lines. Weld growth curves are presented together with results of numerical simulations made in the finite element computer program SORPAS® 3D, which is based on an electro-thermo-mechanical formulation. The numerical models are presented together with the specific modeling conditions leading to numerical simulations in good agreement with experimental results in the range of welding parameters leading to acceptable weld nugget sizes. The validated accuracy of the commercially available software proves the tool useful for assisting the choice of welding parameters. [ABSTRACT FROM AUTHOR]

The challenge of developing a three-dimensional finite element computer program for electro-thermo-mechanical industrial modeling of resistance welding is presented, and the program is applied to the simulation of projection welding of square nuts to sheets. Results are compared with experimental observations and measurements produced by the authors with the aim and objective of assessing the accuracy, reliability and validity of the theoretical and numerical developments. The numerical developments include implementation of friction between deformable objects in the finite element flow formulation in order to model the frictional sliding between the square nut projections and the sheets during the welding process. It is proved that the implementation of friction increases the accuracy of the simulations, and the dynamic influence of friction on the process is explained. [ABSTRACT FROM AUTHOR]

The existing analytical solutions for determining an average coefficient of friction in bending under tension tests are revisited. The most commonly used equations are based on the assumption of uniform pressure in the contact interface, which is proven to be a statically inadmissible assumption. New analytical solutions are presented based on the assumption of concentrated forces, which are shown to be statically admissible. Existing literature supports the existence of localized peaks in the pressure distribution in terms of both numerical simulations and experimental results. Due to the inhomogeneous pressure distribution, bending under tension tests are not considered appropriate for determining the coefficient of friction, but rather a qualitative test capable of relative comparison of tribo-systems. [ABSTRACT FROM AUTHOR]