Extrusion Tests Research Articles

Flow behavior, viscoelastic, textural and foaming characterization of whipped cream: Influence of Lallemantia royleana seed, Salvia macrosiphon seed and carrageenan gums

The effects of sage (Salvia macrosiphon) seed gum (SSG), balangu (Lallemantia royleana) seed gum (BSG) and carrageenan gum were examined on the foaming qualities (foam stability, foam capacity and overrun), viscoelastic properties (frequency sweep test and extrusion test) and flow properties of thickened cream as a function of gum concentration. The flow behavior of the cream samples was fitted to the Herschel-Bulkley model (R2 > 0.95). All samples demonstrated a gel structure with higher G′ (storage modulus) values than the G″ (loss modulus) values. The SSG (at 0.3% concentration) was most effective on viscoelastic properties. Cream samples with 0.1 BSG exhibited foaming properties and a flow behavior similar to the full-fat control sample, i.e. there were no significant differences in either flow (τ0, n, η10) or foaming properties (overrun and foam stability). Results suggest that the formation of a thickened cream (with 30% fat) can acquire properties similar to double cream (55%) when nontraditional gums are added.

Combined extrusion and alkali pretreatment improves grass storage towards fermentation and anaerobic digestion

Grass is an abundant feedstock which is commonly used as animal fodder. It can also be utilized for bio-production, however its availability is generally not consistent through time. Storage is therefore an economic necessity to ensure continuous, steady supply for bioprocessing. Extrusion tests were performed, before or after Ca(OH)2 addition (75, 100 or 200 g kg−1 total solid (TS) of grass), with the objective to achieve 3 months storability without major carbon loss. The performances were determined by the changes in biomass characterisation, methane production through anaerobic digestion and carboxylate production through fermentation, in three storage conditions: fresh (no storage), and afterensiling or wilting for 3 months. For wilting, Ca(OH)2 addition of 100 and 200 g kg−1 TS before extrusion, and 200 g kg−1 TS after extrusion significantly preserved the biomass. For ensiling, the biomass were well preserved. Ensiling with Ca(OH)2 addition of 100 g kg−1 TS before extrusion was found the optimum preservation method in this study, with methane production of 237 ± 10 (test) vs 265 ± 29 (initial control) cm3 g−1 VSinitial CH4, and carboxylate production of 124 ± 8 (test) vs 109 ± 4 (initial control) mg g−1 VSinitial Carbon. Especially when storage conditions were sub-optimal (wilting), addition of 100 g kg−1 TS Ca(OH)2 before extrusion outperformed the non-treated, wilted condition to a large extent (178 ± 18 vs 50 ± 8 cm3 g−1 VSinitial CH4 and 86 ± 17 vs 18 ± 4 mg g−1 VSinitial Carbon). Overall, combined extrusion and alkali pretreatment improves grass storability.

The Effect of Ultrafine-Grained Structure of Al-30Zn on the Shape Forming Ability at Sheet Metal Forming

High pressure torsion (HPT) and equal channel angular pressing in parallel channels (ECAP-PC) at room temperature are used to form homogeneous ultrafine-grained (UFG) structure with a grain size of the aluminum matrix of 350 and 700 nm, respectively, in Al-30Zn (wt. %) specimens. The UFG samples with special geometry produced from the specimens processed by SPD techniques were subjected to sphere-shaped dimple extrusion testing (via the Erikson test method) and bended plate extrusion to determine the material formability during cold sheet metal forming. The same tests were performed on the material with coarse-grained (CG) structure for the sake of comparison. The obtained results are discussed.

Optimum parameters and kinetic analysis for hot working of a solution-treated Mg-Zn-Y-Mn magnesium alloy

The flow behavior, dynamic recrystallization (DRX) evolution and hot workability of the solution-treated Mg94Zn2.5Y2.5Mn1 (at%) alloy were investigated by hot compression tests. Compression tests were performed in the temperature range of 350–500 °C and the strain rate range of 0.001–1 s−1 on a Gleeble-1500D thermo-mechanical simulator. Using regression analysis for the constitutive equation of the flow behavior, the average activation energy of deformation and the stress exponent were determined to be 302.22 kJ/mol and 8.60452, respectively. The flow stress of the Mg94Zn2.5Y2.5Mn1 alloy predicted by the proposed models well agrees with experimental results. The kinetic model of DRX was proposed based on the analysis of true stress-strain data, which can be described as XDRX=1−exp[−2.15((ε−εc)/ε∗)1.51]. The DRX kinetic model was validated by means of microstructure observation. Furthermore, processing maps were developed and analyzed based on the dynamic material model (DMM). The flow instability regions and stability regions were identified based on the processing maps; the optimum domain for hot working of the experimental alloy are temperatures ranging from 400 °C to 450 °C and strain rates ranging from 0.001 s−1 to 0.01 s−1. Finally, a hot extrusion test was performed according to the optimum deformation parameters. The deformed sample exhibited a good surface quality and excellent mechanical properties, which verified the reasonability of the optimal deformation parameters.

Type I Collagen and Strontium-Containing Mesoporous Glass Particles as Hybrid Material for 3D Printing of Bone-Like Materials.

Bone tissue engineering offers an alternative promising solution to treat a large number of bone injuries with special focus on pathological conditions, such as osteoporosis. In this scenario, the bone tissue regeneration may be promoted using bioactive and biomimetic materials able to direct cell response, while the desired scaffold architecture can be tailored by means of 3D printing technologies. In this context, our study aimed to develop a hybrid bioactive material suitable for 3D printing of scaffolds mimicking the natural composition and structure of healthy bone. Type I collagen and strontium-containing mesoporous bioactive glasses were combined to obtain suspensions able to perform a sol-gel transition under physiological conditions. Field emission scanning electron microscopy (FESEM) analyses confirmed the formation of fibrous nanostructures homogeneously embedding inorganic particles, whereas bioactivity studies demonstrated the large calcium phosphate deposition. The high-water content promoted the strontium ion release from the embedded glass particles, potentially enhancing the osteogenic behaviour of the composite. Furthermore, the suspension printability was assessed by means of rheological studies and preliminary extrusion tests, showing shear thinning and fast material recovery upon deposition. In conclusion, the reported results suggest that promising hybrid systems suitable for 3D printing of bioactive scaffolds for bone tissue engineering have been developed.

Estimation of Frictional Coefficient between Punch and Billet at Back-Stroke in Backward Can Extrusion Test of Steel

A backward can extrusion test provides severe tribological conditions because high pressure, high temperature, and large surface expansion ratio affect the lubricant. During the forward stroke these conditions intensify with increasing cup depth of the extruded workpiece; additionally, the back-stroke force during retraction of the punch rises to a significant level under a poor-lubricated condition. This study estimates the coefficient of friction μp between punch and workpiece during the back-stroke by combining experiments using conventional soap-phosphate coated steel and numerical analysis by FEM. The values of μp were estimated to be 0.09 and 0.03 in case of small and large workpiece depth, respectively. Friction decreased with elevating temperature.

Experimental and theoretical analysis of microstructural evolution and deformation behaviors of CuW composites during equal channel angular pressing

CuW composites were synthesized using an equal channel angular pressing (ECAP) technique. Microstructural evolution during sintering process was investigated using both optical microscopy and transmission electron microscopy (TEM), and their deformation mechanisms were studied using finite element analysis (FEA). Results showed severe plastic deformation of the CuW composites and effective refinement of W grains after the ECAP process. TEM observation revealed that the ECAP process resulted in lamellar bands with high densities dislocations inside the composites. Effects of extrusion temperature and extrusion angles on stress-strain relationship and sizes of deformation zones after the ECAP process were investigated both theoretically and experimentally. When the extrusion angle was 90°, a maximum equivalent stress of ~1001 MPa was obtained when the extrusion test was done at room temperature of 22 °C, and this value was lower than compression strength of the CuW composites (1105.43 MPa). The maximum equivalent strains were varied between 0.5 and 0.7. However, when the extrusion temperature was increased to 550 °C and further to 900 °C, the maximum equivalent stresses were decreased sharply, with readings of 311 MPa and 68 MPa, respectively. When the extrusion angle was increased to 135°, the maximum equivalent stresses were found to be 716.9 MPa, 208 MPa, and 32 MPa for the samples extruded at temperatures of 22 °C, 550 °C and 900 °C, respectively. Simultaneously, the maximum equivalent strains were decreased to 0.2–0.4. Furthermore, results showed that the maximum equivalent stress was located on the sample's external surface and the stress values were gradually decreased from the surface to the center of samples, and the magnitudes of plastic deformation zones at the surface were much larger than those at the central part of the sintered samples. FEA simulation results were in good agreements with experimentally measured ones.

Influence of tribological conditions on cold forging of gears

Gears are integral and vital machine elements in the field of drive and transmission technology. With regard to economic and ecological aspects, cold forging represents a promising approach compared to conventional cutting processes for producing highly-loadable gears. A possible extrusion process for manufacturing helical gears is the so-called “Samanta”-process. In comparison to conventional extrusion processes, an additional ejector system is avoidable. Thus, in particular for helical gears, a negative impact on the gear quality by the ejector operation is prevented. Furthermore, the process chain during the component production cycle is shortened which leads to a more efficient production. The achievable gear accuracy as well as insufficient tool life are major challenges while establishing the “Samanta”-process in industry. To enable an industrial application, basic process understanding as well as knowledge about the influences on the process results is required. For influencing component and process properties within cold forging, approaches from the tribological system can be generally used. The aim of this study is to analyze the influence of the friction conditions on selected component and process properties within cold forging of gears by the “Samanta”-process. For adjusting the occurring friction, various lubrication systems were applied, which have been qualified using a double cup extrusion test (DCE-test). The results reveal that the lubrication system determines the friction conditions during forming. Within cold forging of helical gears by the “Samanta”-process, the friction influences the resulting strain hardening of the components and the required maximum forming force as well as the energy amount.

Impact of yeast and fungi (1 → 3)(1 → 6)-β-glucan concentrates on viscoelastic behavior and bread making performance of gluten-free rice-based doughs

The addition of bioactive β-glucan to gluten-free breads is of special interest to people suffering from celiac disease. Most of the studies found in literature involve cereal (1 → 3)(1 → 4)-β-glucan, while those from yeast and fungi are still nearly unexplored. This study focuses on the effect of fortifying gluten-free rice-based doughs and breads with (1 → 3)(1 → 6)-β-glucan concentrates derived from yeasts –soluble (SBG) and insoluble (IBG)– and fungi (Pleurotus Ostreatus) (FBG). SBG-enriched doughs were less firm and exhibited lower resistance to deformation than doughs with FBG or IBG. In contrast, FBG- and IBG-enriched doughs increased their resistance to deformation as the concentration increased. Doughs with a firmer consistency as determined by a forward extrusion test (FBG- and IBG-enriched doughs) corresponded to those with larger dynamic moduli and lower frequency dependence, lower elastic deformation and higher viscosity at steady state. The physical quality of breads was significantly improved by addition of all types of (1 → 3)(1 → 6)-β-glucan at optimized dough hydration. They caused an increase in the specific volume of the breads, a reduction in their hardness and longer shelf-life. Sensory evaluation also demonstrated an improvement in bread organoleptic attributes when SBG was added.

Caracterización de indicadores de la calidad del fruto en líneas de fresa transgénicas con genes silenciados que codifican para enzimas pectinolíticas

Se han evaluado algunos indicadores de calidad del fruto en líneas transgénicas de fresa con los genes de poligalacturonasa FaPG1 (líneas PG) o pectato liasa FaplC (líneas APEL) silenciados. Se analizaron dos líneas independientes por genotipo transgénico. No se observaron diferencias en el contenido de sólidos solubles entre las líneas transgénicas y el control. De igual forma, la acidez total y el pH fueron similares en las líneas PG29, APEL21 y el control; sin embargo, la acidez de los frutos de las líneas PG62 y APEL39 fue superior al control. Los parámetros de color L*, a* y b* fueron similares en todos los genotipos; sin embargo, el contenido en antocianos fue menor en la línea APEL21. Los valores más altos de firmeza de fruto, estimada mediante un ensayo de extrusión, se observaron en las dos líneas transgénicas PG y en la línea APEL39. En cuanto a las pérdidas por goteo (drip loss), la línea APEL39 presentó un valor mayor que el control, pero la línea APEL21 registró valores menores. El contenido de compuestos fenólicos se analizó en la línea PG29, no encontrándose diferencias estadísticas con respecto al control. Finalmente, la capacidad del fruto para captar radicales libres fue ligeramente menor en la línea PG29 que en el control. Los resultados indican que el silenciamiento de los genes de pectinasas incrementa significativamente la firmeza de la fresa sin modificar sustancialmente parámetros de calidad del fruto maduro como color, acidez, sólidos solubles o contenido en antocianos.

Microstructure and mechanical properties of plates warm extruded AZ80Mg alloy fabricated by multi-directional forging in advance

Rectangular-shaped AZ80Mg alloy was multi-directionally forged at decreasing temperature conditions from 623 K down to 433 K at an initial strain rate of 3.0 × 10-3 s-1 to a cumulative strain of ∑Δε = 5.6 at maximum. By multi-directional forging, Mg alloys with having various average grain sizes from 0.7 μm to 26.0 μm were prepared. Then, the multi-directionally forged Mg alloys were further extruded using dies at temperatures between 453 K and 523 K at initial strain rates of 3.0 × 10-4 s-1 and 3.0 × 10-3 s-1 to form plates. Even at such relatively low temperatures, extrusion of the ultrafine-grained Mg alloys could be satisfactory carried out. At some conditions, the values of strain rate sensitivity on loading stress became more than 0.3 indicating occurrence of superplasticity. This result suggested that effect of grain-boundary sliding enabled the warm temperature extrusion of the ultrafine-grained Mg alloys. In such conditions, where lower strain rate, higher temperature and ultrafine-grained structure, slight gain coarsening was also observed. However, the decrease in the strength was quite limited or sometimes further strengthening in contrast took place. This should be caused possibly by combined effects of i) further grain refinement due to dynamic recrystallization, ii) sharp basal texture evolution, iii) dynamic age hardening and iv) work hardening. From the above warm extrusion tests, high strength Mg alloy plates could be successfully produced, therefore, possibility of extrusion of ultrafine-grained Mg alloys with specific high strength at room temperature by employing a mechanism of superplasticity was suggested.

Experimental Approaches to Improve Thermal Stability of Organic Phase Change Properties

This study investigates the thermal behavior of Polyolefin containing Paraffin and Nano Hydrated aluminum silicate Al2Si2O5 (OH) 4 (Kaolin) particles to enhance store energy at ambient temperature. The hybrid Nano composite is based on polyolefin PE as a matrix, whereby paraffin wax and Kaolin were hot blended at varying concentrations. In addition Carbon Nanotube (CNTs) was added in different relative low concentrations to improve the thermal transition among the polymer matrix, since polymer domains are considered as isolator. The composite was prepared by melt mixing using a Brabender Plasrograph and a Two Role Mill. Thermal properties of the composite were determined using DSC and Melt flow Index. Because TES materials are subjected to melting and freezing during life time, multiple extrusion tests to simulate the degradation process of the composite were carried out. FTIR was applied to determine the degradation effect and investigate microstructure changes of the composite. The results obtained demonstrate that the blend shows a tendency to be thermally active at low temperatures. DSC tests evidenced a decrease in melt tempera-ture as a result of increasing Kaolin content and some changes in the latent heat of the compound.

Fabrication of Zr-based bulk metallic glass/aluminum alloy multi-materials by stacking extrusion

Zr-based bulk metallic glass(BMG)/7075 aluminum alloy multi-materials have been successfully fabricated by extrusion in the vertical stacking form. Extrusion tests were carried out at 713 K within the supercooled liquid region(SLR) and the ram speed of 2 mm/min. An interface of which Al alloy is inserted into BMG and wrapped tightly by BMG in the periphery is obtained. The interface between BMG and Al alloy has been characterized by a variety of techniques including Optical Microscope (OM), Scanning Electron Microscope(SEM), X-ray diffraction(XRD) and Transmission Electron Microscope(TEM). The interface is estimated to be defect-free. BMG matrix maintains well amorphous with only a small quantity of nanocrystals at the interface, and elements diffusion is also detected. Both the macrostructure and microstructure analyses indicate a good bonding between dissimilar materials at the interface.

Anisotropic mechanical and physical properties in textured Ti2AlC reinforced AZ91D magnesium composite

The textured 10%volTi2AlC reinforced AZ91D magnesium composite's cross section in parallel (//ED) and perpendicular (⊥ ED) to extruded axis was investigated, compared with the textured AZ91D and as-cast 10%volTi2AlC -AZ91D composite. With the introduction of Ti2AlC particles, the micro-sized Mg17Al12 precipitates previously found in extruded AZ91D became nano-sized and dispersed in composite. This change stimulated the Orowan strengthening effect in yield strength. As Ti2AlC particles were reoriented after hot extrusion, tensile and compressive tests provide evidence of stronger anisotropy in textured composite than the textured AZ91D alloy. At the same time, the different fracture mechanisms were proposed. Furthermore, the changes in slope of the resistivity with temperature (dρ/dT) and electrical resistivity ratio R293K/R77K (RRR) between //ED and ⊥ ED specimens confirm Ti2AlC do contribute in the AZ91 alloy to the scattering of the conductive free electrons.

Competition between intragranular and intergranular deformation mechanisms in ODS ferritic steels during hot deformation at high strain rate

Oxide Dispersed Strengthened (ODS) ferritic stainless steels present well-known fine grains microstructures where dislocation movement is hindered by a dense precipitation of nano-oxides particles. Previous research, on the thermomechanical behavior at high temperature and strain rates, was focused on torsion tests (Karch in J Nucl Mater 459:53–61, 2014). Considering texture evolution and grain shape as indicators of the intragranular dislocation glide activity, it was shown that, for high temperature and strain rate, intragranular deformation was in competition with intergranular accommodation. The latter phenomenon was related to early damaging at grain boundaries. The occurrence of a transition phenomenon from an intragranular to an intergranular deformation mechanism, with increasing temperature, was recently confirmed by neutron diffraction spectroscopy (Stoica in Nature Commun 5:5178, 2014). In the present paper, hot extrusion (HE) tests are performed, avoiding damage due to the high stress triaxiality, and allowing further investigation of intragranular and intergranular plasticity at large strains. Three ferritic steels exhibiting various precipitation size and density were hot extruded. Microstructure evolution at different stages of deformation is investigated using the Electron Back-Scattered Diffraction (EBSD) technique. After extrusion at 1373 K (1100 °C), the microstructure of ODS steels consists of a mixture of small round shape grains and larger elongated grains containing low-angle grain boundaries. Texture measurements show the appearance of the α-fiber ( //extrusion direction) and an increase in its intensity during the extrusion process in the larger grains. The fragmentation of the large elongated grains by Continuous Dynamic Recrystallization (CDRX) partially occurs in ODS materials depending on precipitation reinforcement. For smaller grains, plastic deformation has no effect on crystallographic orientation and grain shape, indicating a grain boundary accommodation phenomenon as the major deformation mechanism. Precipitation density not only impacts the intragranular dislocation glide activity, but also reduces CDRX kinetics in coarse grains.

Inorganic ceramic fiber separator for electrochemical and safety performance improvement of lithium-ion batteries

Abstract A separator based on ceramic fibers with excellent properties, utilized for powerful laminated lithium ion batteries, was prepared by low-cost production process. Physical and chemical characteristics of the separator and the electrochemical as well as the safety performance of lithium ion batteries were extensively investigated, and compared to commercialized polyethylene (PE) and ceramic-coating PE (C-PE) separators. The results demonstrated that inorganic ceramic fiber (CF) membrane exhibited higher porosity (85%), higher electrolyte uptake (381%) and higher ionic conductivity (1.48 mS/cm). Moreover, CF separator did not display thermal shrinkage at 160 °C for 1 h, manifesting that the separator possession of high thermal stability. The lithium nickel cobalt manganese oxide LiNi 0.5 Co 0.2 Mn 0.3 O 2 / graphite battery employing the CF membrane displayed superior rate capability, which delivered the discharge capacities of 13.206 A h (0.2 C), 12.729 A h (0.5 C), and 12.074 A h (1 C), respectively. In addition, this battery improved cycle stability, with the capacity retention of 101.4% following 100 cycles at 1 C rate. Results of safety tests presented that batteries with CF separator passed both nail penetration and extrusion tests, implying that the safety performance was remarkably improved. Additionally, CF membrane had only 20 cents in cost for 1 Ah cells, which was ten times lower than commercial PE and C-PE separators. The perfect combination of good properties and low cost made it possible for the CF separator to be a promising separator for laminated lithium-ion batteries, which are especially used in electric vehicles.

Impact of heat moisture treatment and hydration level on physico-chemical and viscoelastic properties of doughs from wheat-barley composite flours

The impact of heat moisture treatment (HMT) on the thermoviscous, viscoelastic and mechanical properties of binary flour matrices (wheat:barley, 60:40, wt:wt) was investigated in untreated and HMT (15% moisture content, 1 h heating time at 120 °C) hydrated samples to assess the potential of HMT to modify dough viscoelasticity and doughmaking functionality in diluted breadmaking wheat matrices. HMT significance was tackled (a) in excess of water, by applying successive cooking and cooling cycles to hydrated samples (14%, w:w), determination of viscometric parameters, and subsequent determination of textural (compression test) and viscoelastic parameters (stress relaxation test) in pasted and gelled hydrated flours, and (b) under water restrictions by assessing the consistency (forward extrusion test), the primary and secondary mechanical properties (Texture Profile Analysis), and the viscoelastic behaviour (stress relaxation test) of untreated and HMT mixed doughs made at different flour hydration levels (63 and 70%). In highly hydrated blends, HMT barley flour provided enhanced viscosity patterns regardless of the presence of native or HMT wheat flour, and harder gels with larger initial stress to reach a defined deformation, particularly in the presence of HMT wheat flour. Under restricted water availability, doughs made at 70% hydration level when compared to their counterparts made at 63% explicited lower stress relaxation curves with higher values for both initial decay rate and extent of the decay, shorter relaxation times and higher percent of stress relaxation, giving softer and more cohesive doughs. The most elastic-like dough blends were those prepared with HMT wheat and barley flours at 63% hydration, while the most viscous-like doughs were those from native flours made at 70% hydration.

Characterizing the feasibility of processing wet granular materials to improve rheology for 3D printing

Rheological measurements and extrusion tests are used to evaluate the viability of high mass fraction (80% solids content) wet granular materials for extrusion-based 3D printing. Such materials have diverse applications from making dense, strong ceramic custom parts to 3D printing uniquely shaped energetic materials. Traditionally, 3D-printed colloidal materials use much lower mass fraction inks, and hence, those technologies will not work for systems requiring higher mass fraction solids content. These wet granular materials are highly non-Newtonian presenting non-homogenous flows, shear thinning, yield stress, and high elasticity. Such behaviors improve some aspects of print quality, but make printing very difficult. In this work, the relationship between the rheological behavior of wet granular materials and the processing parameters that are necessary for successfully extruding these materials for printing is examined. In the future, such characterizations will provide key indicators on how to alter printer design/operating conditions and adjust material behavior in order to improve printability. This study is a fundamental first step to successfully developing 3D printing technology of wet granular materials.

A novel method for determining friction in cold forging of complex parts using a steady combined forward and backward extrusion test

Forward and backward extrusion are used extensively in the forging industry, and combined forward and backward extrusion occurs during the forging of complex parts. To determine the friction factors in a complex cold forging process, a new method is proposed based on a steady combined forward and backward extrusion test. During this test, extruded specimens without dead zones were obtained, decreasing the required ductility of the testing materials. Consistently obtaining a stable final shape, including the forward rod and the backward cup, is beneficial for standardizing the subsequent measurements. To improve the sensitivity to friction, key parameters that describe the deformation degree of the forward and backward extrusion and the geometry of the punch and die were optimized based on finite-element simulations. After the steady analysis, an improved scheme based on the optimal scheme was obtained as the final design of the steady combined forward and backward extrusion test. From the simulation results, two groups of calibration curves were constructed for different ranges of friction factors. Experiments were carried out to validate the steady combined forward and backward extrusion test. The test procedure was introduced and friction factors were measured for five different lubricants and for dry friction in the cold extrusion of steel. The results from the conventional ring compression test were used in the comparative analysis.

The Influence of Extrusion Process on the Microstructure and Mechanical Properties of Magnesium Alloys

AbstractThe article presents the results of plastic shaping tests of AZ61 and WE43 alloys. There were both classic extrusion tests as well as extrusion tests of KOBO method. An assessment was made of the influence of extrusion process parameters on the mechanical properties and the structure of the alloys. On the basis of achieved results of mechanical properties for alloys AZ31 and WE43 the susceptibility of those alloys to plastic shaping was determined. Quantitative tests of structure assessment in case of alloys AZ61 and WE43 after extrusion with the use of KOBO method were conducted with the use of METILO program. It has been shown that extrusion AZ61, WE43 alloys method KOBO leads to considerable fragmentation of grains.