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New design of the forming equipment DRECE for obtaining UFG structure in strip of sheet

Rusz S., Malanik K., Dutkiewicz J., Cizek L., Donic T., Kedron J., Tylsar S.

Archives of Materials Science and Engineering

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2010

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Vol. 42, nr 2

111-118

EN

Purpose: of this paper is realisation of engineering design and manufacture of new type of equipment DRECE (Dual Rolling Equal Channel Extrusion), designated for obtaining UFG structure in strip of sheet. Design/methodology/approach: The equipment enables refinement of grain in strip of sheet by extrusion technology without change of cross-section. Special attention is paid to the design of the forming tool in order to prevent upsetting of sheet or its undulation during the forming process. Findings: From the viewpoint of design rate of extrusion has been optimised, range of pressure on pressure rolls has been determined, type of lubricant was optimised. Research limitations/implications: In contradiction to classical ECAP process only “A” and “C” type passes can be used. Due to this no shear planes are created in several grid systems and resulting efficiency of SPD process is therefore lower. It is, however, much higher than at rolling process. Practical implications: This equipment can be successfully used in pilot plant and afterwards in industrial practice. The first verification trials have confirmed functionality of this equipment. Originality/value: Development and manufacture of the DRECE equipment were realised at the Technical University of Mining and Metallurgy in Ostrava (VSB-TU Ostrava) in collaboration with designing and manufacturing company. Very realistic pre-requisite exists for obtaining UFG structure in strip of sheet made of non-ferrous metals and their alloys. The development was realised within the frame of the project MPO No. 2A-1TP1/124.

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Influence of change of direction of deformation at ECAP technology on achieved UFG in AlMn1Cu alloy

Rusz S., Malanik K., Dutkiewicz J., Cizek L., Skotnicova I., Hluchnik J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 35, nr 1

21-28

EN

Purpose: of this paper is to extend a complex evaluation of aluminium alloy, which requires very often knowledge of behaviour of deformation at the ECAP process and achieved strengthening, intensity of deformation and very fine structure. These factors have influence on the mechanical properties and formability. Presented knowledge expresses very important information for exploitation of this alloy. Design/methodology/approach: The methods determining the dependencies of force on the route during the ECAP process were used. Achieved values were directly plotted on PC. Findings: Conclusions of this work consisted in determination of structure and mechanical properties of this alloy. Research limitations/implications: Achieved hardness and microstructure of this alloy will be determined by new research. Practical implications: The results may be utilized for determination of a relation between structure and properties of the investigated alloy in the process of manufacturing. Originality/value: These results contribute to complex evaluation of properties of the AlMn1Cu alloy, namely in the light of achievement of very fine - grained structures and corresponding mechanical and forming properties. The results of this paper are determined for research workers – in order to increase efficiency of the process of severe plastic deformation.

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Refining of structure of the alloy AlMn1Cu with use of multiple severe plastic deformation

Rusz S., Malanik K.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 27, nr 2

167-170

EN

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 used at severe plastic deformation.

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Increase of efficiency of the ECAP technology at grain refinement of the alloy AlMn1Cu

Rusz S., Malanik K., Kedron J.

Archives of Materials Science and Engineering

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2008

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Vol. 34, nr 1

52-56

EN

Purpose: The foundation of the resolved problem consists of verification of influence of temperature and also geometry of the ECAP tool on obtaining of required amount of deformation which substantially influences grain size. Research was realised with use of the alloy AlMn1Cu. Verification concerned influence of change or route of deformation on amount of deformation aimed at obtaining of required grain refinement. Design/methodology/approach: At the first stage of solution mathematical simulation was used for determination of conditions for obtaining the required amount of material deformation. Experimental part of the work was then made on the basis of results of the mathematical simulation. Findings: Route of deformation was changed by deflection of horizontal part of the ECAP channel by 10 and 20°. Obtained results were compared with conventional ECAP process without deflection of the channel. Increased efficiency of the ECAP process was confirmed unequivocally. Practical implications: Practical application of the obtained results at forming of the given alloy in the company AlInvest Bridlicna will bring economy of forming operations, as well as operations of heat treatment of that alloy. Originality/value: The obtained results will be verified by designing of new device enabling forming of strip of sheet. This type of alloy is used for production of strip of sheet by technology of successive rolling to the required thickness with required mechanical properties with preservation of the required formability.

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Increasing SPD effectiveness by changing deformation process in the first pass through the ECAP die

Rusz S., Malanik K., Klos M.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 23, nr 2

79-82

EN

Purpose: Purpose of this paper Technology ECAP belongs to the most efficient technologies for production of materials with ultra-fine grained structure. Its disadvantage consists in necessity to make 4 to 5 passes through the channel of forming tool in order to obtain high degree of deformation needed for grain disintegration. Design/methodology/approach: Newly proposed geometry of the channel makes it possible to achieve up to double amount of deformation during the first pass through deformation tool. Findings: In this manner it is possible to obtain much higher efficiency of the whole process. It is a completely new approach to development of this technology. Research limitations/implications: New geometry of tool has been designed which represents the first step toward application of the given equipment in semi-industrial conditions. Practical implications: Obtained results form good pre-requisite for further development of technology for production of ultra-fine grained materials. Originality/value: Achievement of high amount of deformation already at the first pass through the modified ECAP tool. This will create an ultra-fine grained structure, which makes it possible to obtain required mechanical properties of formability with much lower number of passes. New findings will be applied in the field of forming.

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Using severe plastic deformation to prepare of ultra fine-grained materials by ECAP method

Rusz S., Malanik K.

Archives of Materials Science and Engineering

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2007

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Vol. 28, nr 11

683-686

EN

Purpose: The purpose of the paper is to design a tool and propose a procedure for verification of development of structure at equal channel angular pressing. The goal is to obtain after extrusion the semi-products of AlCuMg alloys a fine-grain structure which one hand increases strength properties and plasticity, and on the other hand is possible to use it at selected cases for subsequent deformations under conditions of "super-plastic state". Design/methodology/approach: The experiments were aimed the verification of functionality of the proposed equipment, determination of deformation resistance, deformability and change of structure at extrusion of the alloy AlCu4Mg2. Deformation forces were measured at extrusion. The average grain size in cross direction was determined by quantitative metallographic methods. TEM analysis of the structure of AlCu4Mg2 were also made. Findings: The structural analysis of AlCu4Mg2 alloy made by TEM has demonstrated a perfect suitability of the ECAP die design. The process results in a very fine grain structure (100-200 nm) throughout the sample overall volume, at which the starting average grain size was 150 µm. Practical implications: Aluminium alloys of super fine granularity structure are basic intermediate products realised by ECAP technologies. The state of super fine granularity facilitates forming of material in the so-called 'superplastic state'. The achievement of the desired structure depends primarily on the tool geometry, number of passages through the die, magnitude and speed of deformation, process temperature, and lubrication mode. Originality/value: It has been demonstrated that the extrusion technology is suitable for attaining of grain nano-structure in the material investigated in order to determine the number of extrusion cycles needed and the appropriate canal angle with corresponding internal and external bend radii. The obtained results make for success of further investigative efforts in the area.