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Microstructure evolution in CRCS processed strips of CuCr0,6 alloy

Stobrawa J. P., Rdzawski Z. M., Głuchowski W., Malec W.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 38, nr 2

195-202

EN

Purpose: The aim of this work was to evaluate the ability of a continuous repetitive corrugation and straightening (CRCS) technique in creating ultra fine grained copper-chromium strips as well as to determine the microstructure evolution and its influence on grain size refinement. Design/methodology/approach: Tests were performed with the 0.8 mm thick CuCr0,6 strips using original die set construction. The changes of mechanical properties as well as microstructure evolution versus circles number of deformation were investigated. The microstructure was investigated using optical and electron microscopy (TEM and SEM equipped with EBSD). Findings: The CRCS process effectively reduced the grain size of a CuCr0,6 alloy strips, demonstrating the CRCS as a promising new method for producing ultra fine grained metallic strips. Generally, the mechanism of grain refinement and microstructural evolution during CRCS of CuCr0,6 alloy strips is similar to that observed in other high/medium stacking fault energy materials deformed by SPD, i.e. via dislocation manipulation and accumulation. Any effects connected with mechanical twinning were not observable. Research limitations/implications: Investigation results are limited to the initial material in annealed state. Further investigation should focus on the description of influence of deformation-supersaturation-ageing sequence on strengthening effect. Practical implications: A growing trend to use new copper-based functional materials is recently observed world-wide. Within this group of materials particular attention is drawn to those with ultra fine or nanometric grain size of a copper matrix, which show higher mechanical properties than microcrystalline copper. Originality/value: The paper contributes to the mechanical properties of precipitates strengthened ultra fine grained copper - chromium alloy strips obtained by original RCS method and to the microstructure evolution.

2

Mechanical properties of ultra-fine grain titanium

Greger M., Widomska M., Kander L.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 40, nr 1

33-40

EN

Purpose: The main goal of the presented paper was to describe deformation behaviour of the commercial purity titanium during the ECAP method. Attention was paid particularly on reached mechanical properties of above mentioned material. Design/methodology/approach: Design of experiments rested in extrusion at temperature in range from room temperature up to 280°C. The way of approach was planned in investigation of imposed strain accumulation ability. Among used methods for determination of intended aims were tensile tests, TEM, SEM. Findings: Depending on imposed strain (e = 2 up to 8) was found that mechanical properties (namely tensile strength) have increased up to 960 MPa. Research limitations/implications: Developed ECAP process enables controlling morphology of microstructural constituents and workability of commercially pure titanium. Practical implications: Obtained findings may be used in process of preparing materials for medical application such as dental application where is very important factor their sensitivity to strain. Originality/value: Value of paper is mainly in observed findings that can be used in determination of process conditions at submicro or ultra-fine crystalline materials.

3

Microstructure evolution in CRCS processed strips of CuCr0,6 alloy

Stobrawa J.P., Rdzawski Z.M., Głuchowski W., Malec W.

Archives of Computational Materials Science and Surface Engineering

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2010

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Vol. 2, nr 3

125-132

EN

Purpose: The aim of this work was to evaluate the ability of a continuous repetitive corrugation and straightening (CRCS) technique in creating ultra fine grained copper-chromium strips as well as to determine the microstructure evolution and its influence on grain size refinement. Design/methodology/approach: Tests were performed with the 0.8 mm thick CuCr0,6 strips using original die set construction. The changes of mechanical properties as well as microstructure evolution versus circles number of deformation were investigated. The microstructure was investigated using optical and electron microscopy (TEM and SEM equipped with EBSD). Findings: The CRCS process effectively reduced the grain size of a CuCr0,6 alloy strips, demonstrating the CRCS as a promising new method for producing ultra fine grained metallic strips. Generally, the mechanism of grain refinement and microstructural evolution during CRCS of CuCr0,6 alloy strips is similar to that observed in other high/medium stacking fault energy materials deformed by SPD, i.e. via dislocation manipulation and accumulation. Any effects connected with mechanical twinning were not observable. Research limitations/implications: Investigation results are limited to the initial material in annealed state. Further investigation should focus on the description of influence of deformation-supersaturation-ageing sequence on strengthening effect. Practical implications: A growing trend to use new copper-based functional materials is recently observed world-wide. Within this group of materials particular attention is drawn to those with ultra fine or nanometric grain size of a copper matrix, which show higher mechanical properties than microcrystalline copper. Originality/value: The paper contributes to the mechanical properties of precipitates strengthened ultra fine grained copper -chromium alloy strips obtained by original RCS method and to the microstructure evolution.

4

Ultrafine grained strips of CuCr0.6 alloy prepared by CRCS method

Stobrawa J. P., Rdzawski Z. M., Głuchowski W., Malec W.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 33, nr 2

166-172

EN

Purpose: The aim of this work was to evaluate the ability of a continuous repetitive corrugation and straightening (CRCS) technique in creating ultra fine grained copper-chromium strips as well as to determine their deformability, mechanical properties, deformation behaviour and microstructure evolution. Design/methodology/approach: Tests were performed with the 0.8 mm thick CuCr0.6 strips using original die set construction. The changes of mechanical properties as well as microstructure evolution versus number of deformation cycles were investigated. The microstructure was investigated using optical and electron microscopy (TEM and SEM equipped with EBSD). Findings: The obtained strengthening effects and observed microstructure changes have been discussed basing on the existing theories related to strengthening of ultra fine grained copper based materials. The CRCS process effectively reduced the grain size of a CuCr0.6 alloy strips, demonstrating the CRCS as a promising new method for producing ultra fine grained metallic strips. Research limitations/implications: Research results are limited to the initial material after annealing only. Further investigations should be aimed towards determination of CRCS sequence including deformation-precipitation-ageing influence on strengthening effect. Practical implications: A growing trend to use new copper-based functional materials is observed recently world-wide. Within this group of materials particular attention is drawn to those with ultra fine or nanometric grain size of a copper matrix, which exhibit higher mechanical properties than microcrystalline copper. Originality/value: The paper describes to the mechanical properties of precipitates strengthened ultra fine grained copper - chromium alloy strips obtained by original RCS method and to the microstructure evolution.

5

Microstructure and properties of CuNi2Si1 alloy processed by continuous RCS method

Stobrawa J., Rdzawski Z., Głuchowski W., Malec W.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

466-479

EN

Purpose: Precipitation strengthened copper constitutes a group of functional and structural materials used where combination of high electrical conductivity with high strength is required. A growing trend to use new copper-based functional materials is recently observed world-wide. Within this group of materials particular attention is drawn to those with ultrafine grain size of a copper matrix. Design/methodology/approach: This study was aimed to investigate mechanical properties and microstructure in strips of age hardenable CuNi2Si alloy processed by continuous repetitive corrugation and straightening (CRCS). Tests were performed with quenched (900°C/1hour/water) or annealed (650°C /1 hour) 0.8 mm thick strips using original die set construction (toothed rolls and plain rolls set) installed in tensile testing machine. The changes of mechanical properties (HV, ultimate tensile strength, 0.2 yield strength) as well as microstructure evolution versus number of deformation cycles were investigated. The microstructure was investigated by optical and electron microscopy (TEM and SEM equipped with EBSD). Findings: The obtained strengthening effects and observed microstructure changes have been discussed basing on the existing theories related to strengthening of ultra fine grained copper based materials. Practical implications: The CRCS process effectively reduced the grain size of CuNi2Si1 alloy strips especially for annealed material, demonstrating the CRCS as a promising new method for producing ultra fine grained metallic strips. Originality/value: The paper contributes to the mechanical properties of precipitation strengthened ultra fine grained copper - chromium alloy strips obtained by original RCS method and to the microstructure evolution.

6

Otrzymywanie oraz badanie materiałów ultradrobnoziarnistych i nanokrystalicznych za pomocą jednostki MAXStrain Symulatora GLEEBLE 3800

Zalecki W., Kuziak R., Łapczyński Z., Molenda R., Wojtas J., Suś-Ryszkowska M., Pakieła Z.

Prace Instytutu Metalurgii Żelaza

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2005

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T. 57, nr 4

7-14

PL

Celem pracy było zbadanie wpływu parametrów odkształcenia (temperatury, wielkości i prędkości odkształcenia) na kształtowanie struktury stopu AA6061, stali austenitycznej 316L oraz materiału intermetalicznego na bazie stopu Fe-Al i wpływu rozdrobnienia mikrostruktury na własności mechaniczne. Badania stopu AA6061 miały na celu określenie równoczesnego oddziaływania odkształcenia i grzania na ewolucję mikrostruktury stopu. W wyniku przeprowadzonych badań określono warunki obróbki cieplno-plastycznej pozwalające na uzyskanie struktur drobnoziarnistych i nanokrystalicznych badanych materiałów.

EN

The purpose of this paper is to investigate the influence of deformation parameters (temperature, strain and strain rate) on forming the structure of AA6061 alloy, 316L austenitic steel and intermetallic material based on Fe-Al alloy, as well as influence of microstructure refinement on mechanical properties. The aim of the tests carried out for AA6061 alloy was to determine simultaneous influence of deformation and heating on the alloy microstructure evolution. The tests resulted in determination of thermo-plastic treatment conditions that allowed fine-grained and nanocrystalline structures to be obtained in tested materials.