The paper presents results of FEM modelling as well as properties and microstructure of the ultralow-carbon ferritic steel after the unconventional SPD process—DRECE (dual rolls equal channel extrusion). Based on the conducted numerical... more
The paper presents results of FEM modelling as well as properties and microstructure of the ultralow-carbon ferritic steel after the unconventional SPD process—DRECE (dual rolls equal channel extrusion). Based on the conducted numerical simulation information about the deformation behaviour of a steel strip during the DRECE process was obtained. The simulation results were experimentally verified. The influence of DRECE process on hardness distribution, fracture behaviour and microstructure evolution of the investigated steel was analysed. The increase of steel strength properties after subsequent deformation passes was confirmed. The microstructural investigations revealed that the processed strips exhibit the dislocation cell microstructure and subgrains with mostly low-angle grain boundaries. The grains after processing had relatively high dislocation density and intense microband formation was observed. It was also proved that this unconventional SPD method fosters high grain re...
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The paper is aimed on appraisal of influence of preceding deformation on spring steel CCT diagrams, which were created on the basis on dilatometric analyses of cooling curves, using universal plastometer Gleeble 3800, CCT and DCCT... more
The paper is aimed on appraisal of influence of preceding deformation on spring steel CCT diagrams, which were created on the basis on dilatometric analyses of cooling curves, using universal plastometer Gleeble 3800, CCT and DCCT diagrams after austenitisation at the temperature of 850 °C, which were further supported by metallographic analyses and hardness measurements HV30. Dilatometric tests were performed at different cooling rates in the range from 0.16 to 12 °C/s. The diagrams prepared in this way were compared with the diagrams computed numerically by the specialised software QTSteel under the same conditions. The comparison of the experimentally obtained diagrams with the numerically computed ones confirms irreplaceability of physical experiments due to big differences between reality and numerically computed diagrams. The influence of preceding deformation on anisothermal disintegration of austenite was manifested at each phase transformation, but in case of pearlitic tran...
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In the selective laser melting process (SLM), the region irradiated by the laser beam is melted and quickly solidified, forming solidification lines (laser scan tracks) with symmetrical shapes. Because of the unique (rapid)... more
In the selective laser melting process (SLM), the region irradiated by the laser beam is melted and quickly solidified, forming solidification lines (laser scan tracks) with symmetrical shapes. Because of the unique (rapid) crystallization conditions, the subgrain structures, typically observed inside these solidification lines, could also have variable geometric symmetrical patterns, e.g., cellular, pentagonal, or hexagonal cellular. The existence of such distinctive microstructures in SLM-made alloys has a significant impact on their superior mechanical and corrosion properties. Thus, any modification of this symmetrical microstructure (due to post-processing) can degrade or improve the properties of SLM-fabricated alloys. This study presents the experimental results on the effects of heat treatment and ECAP on microstructure modification and corrosion behavior of SLM-fabricated AlSi10Mg alloy. Light microscopy, scanning electron microscopy (SEM), electron backscattered diffractio...
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This article presents a study on the effect of strain rate, specimen orientation, and plastic strain on the value and distribution of the temperature of dog-bone 1 mm-thick specimens during their deformation in uniaxial tensile tests.... more
This article presents a study on the effect of strain rate, specimen orientation, and plastic strain on the value and distribution of the temperature of dog-bone 1 mm-thick specimens during their deformation in uniaxial tensile tests. Full-field image correlation and infrared thermography techniques were used. A titanium-stabilised austenitic 321 stainless steel was used as test materials. The dog-bone specimens used for uniaxial tensile tests were cut along the sheet metal rolling direction and three strain rates were considered: 4 × 10−3 s−1, 8 × 10−3 s−1 and 16 × 10−3 s−1. It was found that increasing the strain rate resulted in the intensification of heat generation. High-quality regression models (Ra > 0.9) developed for the austenitic 321 steel revealed that sample orientation does not play a significant role in the heat generation when the sample is plastically deformed. It was found that at the moment of formation of a necking at the highest strain rate, the maximum sampl...
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ABSTRACT Microstructure and texture evolution in equal channel angular extrusion (ECAE) of interstitial-free (IF) steel is investigated for up to 4 passes via routes A, BA, BC and C. Observations by transmission electron microscopy reveal... more
ABSTRACT Microstructure and texture evolution in equal channel angular extrusion (ECAE) of interstitial-free (IF) steel is investigated for up to 4 passes via routes A, BA, BC and C. Observations by transmission electron microscopy reveal that the efficacy of grain refinement depends on both processing route and pass number. The preferred route is found to be route C after 2 passes but route BC after 4 passes. Quantitative analysis of the experimental textures shows the development of {1 1 0}〈u v w〉θ and {h k l}〈1 1 1〉θ partial fiber textures in all routes, but the orientation distribution along these fibers is more uniform in routes A and C than BA and BC. The experimental textures are well predicted using a visco-plastic self-consistent model based on the simple shear assumption of ECAE deformation. Finite element (FE) analysis and further texture simulations using the FE-predicted deformation history suggest that imperfect strain reversal is a main factor for the prevalence of shear-type textures and elongated lamellar substructure observed after the even-numbered passes of route C.
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This research paper shows the influence of a repeated SPD (Severe Plastic Deformation) plastic forming with the DRECE technique (Dual Rolls Equal Channel Extrusion) on hardening of low carbon IF steel. The influence of number of passes... more
This research paper shows the influence of a repeated SPD (Severe Plastic Deformation) plastic forming with the DRECE technique (Dual Rolls Equal Channel Extrusion) on hardening of low carbon IF steel. The influence of number of passes through the device on change of mechanical properties, such as tensile strength TS and yield stress YS, of tested steel was tested. The developed method is based on equal channel extrusion with dual rolls and uses a repeated plastic forming to refinement of structure and improve mechanical properties of metal bands [1-2]. For the tested steel the increase of strength properties after the DRECE process was confirmed after the first pass in relation to the initial material. The biggest strain hardening is observed after the fourth pass.
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The article describes a new developed method for producing fine-grained materials, such as DRECE (DRECE, Dual Rolling Equal Channel Extrusion). It describes the process of forming of metal sheets made of steel grade 11 321. It further... more
The article describes a new developed method for producing fine-grained materials, such as DRECE (DRECE, Dual Rolling Equal Channel Extrusion). It describes the process of forming of metal sheets made of steel grade 11 321. It further describes two methods for detection of deep drawing - Erichsen and Fukui. These methods were applied to the extruded metal sheet by DRECE tools. The article presents the results of both exams, including photographs of cracks. Mechanical properties of the steel grade 11 321 before and after extrusion by DRECE tool are described as well.
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The paper presents results of investigations of mechanical properties and micro-structure specimens made of AZ31 magnesium alloy after the ECAP processing. These properties and micro-structure are influenced by technological factors... more
The paper presents results of investigations of mechanical properties and micro-structure specimens made of AZ31 magnesium alloy after the ECAP processing. These properties and micro-structure are influenced by technological factors during application of the ECAP method, namely by selection of suitable temperature for processing. The ECAP tool is presented by new shape geometry of channel. Measurement of micro-hardness showed an increased value after application of higher number of passes in agreement with high occurrence of fine grains.
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At the contemporary stage of the development of the engineering thought, and the product technology itself, material engineering has entered the period of new possibilities of designing and manufacturing of elements, introducing new... more
At the contemporary stage of the development of the engineering thought, and the product technology itself, material engineering has entered the period of new possibilities of designing and manufacturing of elements, introducing new methods of melting, casting, forming, and heat treatment of the casting materials, finding wider and wider applications in many industry branches. Engineers whose employment calls for significant expenditure of labour and costs strive to reduce material consumption. Therefore the development of engineering aims at designs optimizing, reducing dimensions, weight, and extending. Increasing the share of light structural materials in structures of airplanes or vehicles leads to reduction of environmental load. Magnesium alloys also play an important role among these materials. Aluminium and zinc are used the most frequently for alloying of magnesium. Small concentrations of manganese in the Mg-Al-Zn alloys improve resistance of these alloys to corrosion. All...
The technology, ECAP – Equal Channel Angular Pressing, belongs to technologies of accelerated development and it represents a top item R&D agenda in the world. This technology represents a basic method for achieving super fine granularity... more
The technology, ECAP – Equal Channel Angular Pressing, belongs to technologies of accelerated development and it represents a top item R&D agenda in the world. This technology represents a basic method for achieving super fine granularity structures. Especially non-ferrous metals and their alloys are of primary concern. Non-ferrous metals, and their alloys are subject of an easy recycling process, and they increasingly tend to substitute steel on a larger scale. At the same time, a major decrease of production cost for these materials, and their products can be noted. Their importance for applications by automobile industry is ever growing that is also the case for military and space industries.
Device “DRECE - Dual Rolls Equal Channel Extrusion” is used for production of metallic materials with very fine grain size (UFG). During the actual forming process the principle of severe plastic deformation is used. Metallic strip with... more
Device “DRECE - Dual Rolls Equal Channel Extrusion” is used for production of metallic materials with very fine grain size (UFG). During the actual forming process the principle of severe plastic deformation is used. Metallic strip with dimensions 57×2×1000 mm is inserted into the device. During the forming process the main cylinder in synergy with the pressure roller extrude the material through the forming tool without any change of cross section of the strip. In this way a significant refinement of grain is achieved by severe plastic deformation. This method is used for various types of metallic materials, non-ferrous metals and their alloys. The DRECE device is also being verified from the viewpoint of achievement of a UFG structure in a blank of circular cross-section (wire) with diameter of ϕ 8 mm × 1000 mm.
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On the basis of the uniaxial compression tests realized in the temperature range from 800 °C to 1200 °C and at strain rates from 0.05 s-1 to 30 s-1 the value of the activation energy at hot forming of coarse-grained as-cast iron aluminide... more
On the basis of the uniaxial compression tests realized in the temperature range from 800 °C to 1200 °C and at strain rates from 0.05 s-1 to 30 s-1 the value of the activation energy at hot forming of coarse-grained as-cast iron aluminide Fe40at.%Al-Zr-B was calculated as Q = 502 kJ·mol-1. With use of this material constant, relatively precise mathematical description of the maximum flow stress and the corresponding strain in dependence on the Zener-Hollomon parameter was possible. As was discovered by metallographical analysis, at high values of the Zener-Hollomon parameter slight decrease in flow stress occurs even without significant course of dynamic recrystallization.
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Development of materials with ultra-fine structure, i.e. nano-structural materials, belongs nowadays to front-end areas of research of materials and forming technologies all over the world. This topic is also one of the leading themes of... more
Development of materials with ultra-fine structure, i.e. nano-structural materials, belongs nowadays to front-end areas of research of materials and forming technologies all over the world. This topic is also one of the leading themes of the EU 7th Framework program. Substance of this process consists in obtaining of grain size of tested material under 1 μm. Sub-microcrystalline materials with average grain size from 50 to 200 (nm) are characterised by very high formability with preservation of their very good strength properties. Important part of works of existing research centres deals with issues of strengthening in the course of plastic deformation. Main content of work will consist of verification of new technology of manufacturing of nano-structural materials by so called EHSD method Extrusion with High Stage of Deformation with use of Al alloys. Moreover there will be made a comparison of the obtained results with currently published research works in this area, as well as m...
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One of the ways to the more effective use of metallic materials consists in their processing by forming. At present in this the area the process of severe plastic deformation (SPD process) is used, leading to a refinement of the structure... more
One of the ways to the more effective use of metallic materials consists in their processing by forming. At present in this the area the process of severe plastic deformation (SPD process) is used, leading to a refinement of the structure (materials with UFG structure). The main goal of the paper is a review of the current achieved results obtained by processing of magnesium alloy AZ31 by ECAP technology with use of the prototype tool, which was put into service at the Department of Mechanical Technology, VSB-Technical University of Ostrava. The paper describes results of determination of an influence of number of passes through the ECAP tool with helix matrix on the resulting mechanical and micro-structural properties of the processed magnesium alloy AZ31 in the as-cast state and after selected heat treatment methods.
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This article presents a study on the influence of temperature and time of multi-variant heat treatment on the structure and properties of materials produced in direct metal laser sintering (DMLS) and casting technology. The materials were... more
This article presents a study on the influence of temperature and time of multi-variant heat treatment on the structure and properties of materials produced in direct metal laser sintering (DMLS) and casting technology. The materials were manufactured in the form of cuboidal elements with a cross-section of 1.5 mm × 15 mm and a length of 60 mm. The samples prepared in this way had a similar volume, but due to the production technology the metal crystallization took place at different rates and directions. In the cast, the direction of heat transfer was toward the mold, and the DMLS was directed locally layer by layer. The small thickness of the cast material allowed reaching conditions similar to the DMLS cooling process. Both DMLS and cast samples show similar mechanical properties (hardness) achieved after long ageing time, i.e., 16 h at 170 °C. The maximum hardness was observed for 8 h. In the DMLS samples, in contrast to cast samples, no lamellar precipitates of silicon were obs...
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ABSTRACT Commercial brass Ms36, 2mm thick was annealed and deformed in 6 passes in dual rolls equipment with attached equal channel equipment (DRECE). Then, material was deformed again using constrained groove pressing (CGP) by pressing... more
ABSTRACT Commercial brass Ms36, 2mm thick was annealed and deformed in 6 passes in dual rolls equipment with attached equal channel equipment (DRECE). Then, material was deformed again using constrained groove pressing (CGP) by pressing of grooves 4.2 mm thick, and the groove angle of 45 deg. The experiment was performed 8 times (pressing out grooves and straightening at room temperature). Both methods allowed deformation without changing of the thickness of the sample, which was almost constant near 2 mm. The tensile experiment have shown the Yield Strength YS after 8x groove pressing of 210 MPa and Ultimate Tensile Strength UTS increased 27% up to 430 MPa. At the same time total elongation decreased from 34 to 15 %. The structure of the material after DRECE 6 passes was investigated using conventional TEM and have shown only rather uniform distribution of dislocations. After additional 8 groove pressing experiment, frequent, narrow deformation twins were observed accompanied by the formation of subgrains. Orientation imaging microscopy performed have shown average grain size after DRECE process near 5 μm, which decreased after 8 processes of groove pressing down to 2.9 μm. The fraction of low angle boundaries (below 5 deg) decreased after groove pressing down to 73% from 85% after DRECE process and annealing, while the fraction of high angle grain boundaries (>15 deg) increased after groove pressing up to 24% from 14%, however the total length of high angle boundaries increased more than 2 times since grain size decreased. The structure studies have shown rather mild effect on the grain refinement of both methods and they have to be modified to obtain material approaching nanosize range.
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One of the boisterously developing areas is the development of nano-structural materials, which at present belongs to the priority areas of scientific research aimed at materials and also at forming technologies all over the world.... more
One of the boisterously developing areas is the development of nano-structural materials, which at present belongs to the priority areas of scientific research aimed at materials and also at forming technologies all over the world. Significance of use of these materials grows especially in automotive industry, in military and space industries. This paper informs namely on ECAP technology investigations that have been oriented by overall objectives of acquiring new knowledge concerning deformation resistances, stress condition impacts and structure and properties of nonferrous metals and its alloys. Magnesium - zirconium alloy and WE43 magnesium alloy for investigation was used.
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This paper shows results of researches of a structure and mechanical properties of metal sheets of IF steels subjected to recrystallization annealing. The annealing was held in the scope of the temperature of 600-900°C over 25 min time.... more
This paper shows results of researches of a structure and mechanical properties of metal sheets of IF steels subjected to recrystallization annealing. The annealing was held in the scope of the temperature of 600-900°C over 25 min time. The impact of heat treatment on changes of properties and structure of the researches steel has been analysed. During annealing typical processes of rebuilding of the structure deformed as a result of cold deformation in the form of forming new recrystallized grains and their growth were observed. As the temperature of annealing increases the hardness of the material gradually decreases.
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Purpose: Substance of the investigated issue is analysis of the obtained medium grain size, mechanical properties and formability of the alloy AlCu1Mn by the process of multiple severe plastic deformation. Design/methodology/approach:... more
Purpose: Substance of the investigated issue is analysis of the obtained medium grain size, mechanical properties and formability of the alloy AlCu1Mn by the process of multiple severe plastic deformation. Design/methodology/approach: Comparison of results obtained by pressing through the classical channel geometry and through the channel with modified geometry. Findings: This alloy is used for manufacture of strips. Obtaining of the required grain refinement during initial forming operations will substantially change the existing production technology and increase its efficiency. Research limitations/implications: Increase of amount of deformation will fundamentally increase efficiency of the process of multiple severe plastic deformation. Practical implications: New findings will be applied into production technology at the company AlInvest Bridlicna, Czech Republic. Originality/value: New solution of geometry of the ECAP channel is original, as well as findings, which will be use...
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Technology ECAP is at present the most verified technology for manufacture of UFG and nano-materials. Dependencies of impact of geometry of the ECAP channel on gradual achievement of high degree of deformation (e ≈ 4 − 5) are well known.... more
Technology ECAP is at present the most verified technology for manufacture of UFG and nano-materials. Dependencies of impact of geometry of the ECAP channel on gradual achievement of high degree of deformation (e ≈ 4 − 5) are well known. For achievement of this high deformation it is necessary to choose also an optimum type of passes through the ECAP tool in dependence on the formed material. The paper analyses influence of changes of the deformation routes on magnitude of intensity of deformation and intensity of stress. Change of route of deformation is realised by new geometry of horizontal channel, which consists of classical square cross section followed by helix, while the outlet has also a square cross section. On the semis made of Al we have achieved an increase of intensity of deformation by 25-30% at individual passes. Mathematical simulation was realised in the program Simufact Forming. The obtained results were mutually compared. Efficiency of the SPD process was substan...
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Purpose: In the following paper there have been the structure and fatigue properties of micro-alloyed 23MnB4 steel in initial state and after heat treatment evaluated. Design/methodology/approach: Fatigue test of micro-alloyed 23MnB4... more
Purpose: In the following paper there have been the structure and fatigue properties of micro-alloyed 23MnB4 steel in initial state and after heat treatment evaluated. Design/methodology/approach: Fatigue test of micro-alloyed 23MnB4 steel was completed by metallographic and fracture analyses. For scope the methods of the light microscopy and SEM were used. Findings: Microstructure of examined alloy in initial state was characterized mostly by fine ferrite with pearlitic net and in state after heat treatment was formed by martensite or partly by bainite and after tempering was formed by tempered martensite. Objective of this work consisted in determination of fatigue characteristics of micro-alloyed 23MnB4 steel, including fracture analyze. Results of fatigue testing at various stress levels for the samples in initial state and after the heat treatment have confirmed that obtained values of cycles to rupture were at least 585 000 cycles. Change of fatigue properties in dependence on...
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The microstructure that is attributable from the specific casting method dictates further mechanical and physical properties of the material. In order to understand how to control the microstructure of the casting, it is important to... more
The microstructure that is attributable from the specific casting method dictates further mechanical and physical properties of the material. In order to understand how to control the microstructure of the casting, it is important to understand the changes in microstructure during crystallization. The work focused on thermal analysis, metallurgical characterization and laser treatment of an aluminium alloy. The research show that the thermal analysis carried out on UMSA Technology Platform is an efficient tool for collect and calculates thermal parameters. The paper contributes to better understanding non-equilibrium metallurgical characterization of aluminium alloys. The solidification of the aluminium dendritic network, iron containing intermetallic phases, the aluminium-silicon eutectic and magnesium containing intermetallic phases were characterized.
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Rozwoj technologii produkcji materialow ultra drobnoziarnistych jest obecnie bardzo intensywnie przyspieszany. Na VSB – Uniwersytecie Technicznym w Ostravie opracowano metode, ktora wykorzystuje zasade powtarzalnej obrobki plastycznej w... more
Rozwoj technologii produkcji materialow ultra drobnoziarnistych jest obecnie bardzo intensywnie przyspieszany. Na VSB – Uniwersytecie Technicznym w Ostravie opracowano metode, ktora wykorzystuje zasade powtarzalnej obrobki plastycznej w celu rozdrobnienia struktury i poprawy wlaściwości mechanicznych taśm blachy metalowej. Najwieksze praktyczne znaczenie ma wzrost umownej granicy plastyczności oraz granicy wytrzymalości taśm blachy metalowej. Nowo opracowaną metode stanowi wyciskanie rownokanalowe podwojnymi rolkami (DRECE). Powtarzalna obrobka plastyczna (SPD) skutkuje wysokim stopniem przetworzenia materialu. Metode te mozna stosowac do produkcji materialow metalicznych o bardzo drobnoziarnistej strukturze (dalej zwanej strukturą ultradrobnoziarnistą). Proces ksztaltowania jest oparty na technologii wyciskania z zerową redukcją grubości taśmy blachy z koncowym celem osiągniecia wysokiego stopnia odksztalcenia w formowanym materiale, co skutkuje znaczną poprawą wlasności mechaniczn...
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Currently, technological progress in many modern industries requires in implementation of new types of technical materials and related development of new manufacturing technologies that bring both enhancement of service properties of... more
Currently, technological progress in many modern industries requires in implementation of new types of technical materials and related development of new manufacturing technologies that bring both enhancement of service properties of final products, as well as their wider implementation into engineering practice, including the associated energy savings. One possibility is also a constant increasing of consumption of non-ferrous metals. Sustainable development of human society is subject to a maximum economy of non-renewable sources of energy and raw materials, especially metallic ones. One of the ways for achieving this goal, in addition to recycling waste alloys based on aluminium, copper and magnesium, is systematic reduction of their consumption by increasing their quality and service life of utility objects and structures made from them. One of the ways to the more effective use of metallic materials is their processing by forming. At present in this the area the use of the proc...
The main goal of the paper is a review of current achieved results given by processing of Cubased materials by DRECE technology, whose prototype equipment has been put in service in the end of 2008 at VSB-Technical University of Ostrava,... more
The main goal of the paper is a review of current achieved results given by processing of Cubased materials by DRECE technology, whose prototype equipment has been put in service in the end of 2008 at VSB-Technical University of Ostrava, Faculty of Mechanical Engineering and Dept. of Mechanical Technology. Two types of Cu-based materials – technical pure Cu (99,5 % purity) and brass in α modification – have been used like an experimental materials. The paper describes results of determination of an influence of pass number on output mechanical and micro structural properties of processed Cu-based materials. The paper shows some demonstration of a micro structural evaluation with using of light microscopy and TEM. The paper also shows proposals for testing procedures for determination of UFG materials micro structural stability after ECAP process by AlMn1Cu and AlFe1,5Mn alloys. First method is based on determination of critical temperature given from observed changes of mechanical p...
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The paper presents achieved results given by practical testing of Al-based materials – AlMn1Cu and AlFe1,5Mn – processed by ECAP with modified channel angle. This mechanical properties evaluation was carried out according to already... more
The paper presents achieved results given by practical testing of Al-based materials – AlMn1Cu and AlFe1,5Mn – processed by ECAP with modified channel angle. This mechanical properties evaluation was carried out according to already presented coordinated testing method that had been developed during the solving of R&D project under a cooperation with VŠB-TUO, FS. These aproaches represent an optimalization of standardized mechanical testing methods for usual dimensional and geometrical specifications of UFG materials regarding to its properties. Testing results given in the paper especially include results by tensile test with using of a modified – substandard dimensions testing specimens and a small-punch test, also with demostration of its cross-correlation. The paper also presents UFG microstructure stability evaluation method that had been proposed during solving the project. 1. MAIN GOAL The main goal of the paper is short introduction to proposed aproaches for evaluation of me...
Achievement of ultra-fine grained (UFG) structure in the strip of sheet is one of the basic problems of the current research in the field of forming. Contrary to bulk forming (processes ECAP, HPT, Conform, etc.), it is much more difficult... more
Achievement of ultra-fine grained (UFG) structure in the strip of sheet is one of the basic problems of the current research in the field of forming. Contrary to bulk forming (processes ECAP, HPT, Conform, etc.), it is much more difficult to achieve high degree of deformation during 5 to 7-8 passes by the processes ARB, C2S2 (DCAP). At extrusion of the strip of sheet with use of the process C2S2 the refinement of structure (e.g., in the sheet made of Al) is visible only after 12-15 passes. This is given by the possibility of use of only one type of passes designated in literature as ”C” (pass with turning of material by 180°). This creates smaller number of different types of shear planes than at the passes of the type ”Bc”. The paper gives an analysis of influence of number of passes on structure refinement of a strip of Al sheet on the brand new prototype equipment, DRECE (Dual Rolling Equal Channel Extrusion). The process was mathematically simulated and results were mutually com...
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This research concerned the whole production of UFG materials, using Severe Plastic Deformation (SPD). Use of these materials is very versatile – either directly as semi-products for subsequent further processing with lower number of... more
This research concerned the whole production of UFG materials, using Severe Plastic Deformation (SPD). Use of these materials is very versatile – either directly as semi-products for subsequent further processing with lower number of operations (created structure is preserved in final products), or for production of final products from semi-products. Contribution concerned the whole production of UFG materials, using forming process DRECE (Dual Rolls Equal Channel Extrusion). The strip sheet with dimensions of 58 x 2 x 1000 mm is inserted into the workspace and forced by feed roller with help presser rollers to the forming tool. There is intensive plastic deformation. Cross-section and length of the strip stays unchanged. Forming process is repeated several times. Severe plastic deformation realized in this way it allows to refinement of the structure. He also evaluated the influence of heat treatment on the mechanical properties and structure. The values of hardness of the formed s...