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1

Structure of rolled CuTi4 alloy

Konieczny J., Rdzawski Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 50, nr 1

26--39

EN

Purpose: The aim of the work is to investigate the microstructure of the heat treated and cold rolled commercial CuTi4 copper alloy. Design/methodology/approach: Observations an investigations of the structure were made on the JOEL transmission electron microscope (TEM), scanning electron microscope (SEM) Zeiss SUPRA 25 and diffractometer X’Pert Panalytical. Findings: Decomposition of supersaturated solid solution in that alloy is similar to the alloys produced in laboratory scale. The observed differences in microstructure after supersaturation were related to the presence of undissolved Ti particles and increased segregation of titanium distribution in copper matrix including microareas of individual grains. The mentioned factors influence the mechanism and kinetics of precipitation and subsequently the produced wide ranges of functional properties of the alloy. Research limitations/implications: Cold deformation (50% reduction) of the alloy after supersaturation changes the mechanism and kinetics of precipitation and provides possibilities for production of broader sets of functional properties. It is expected that widening of the cold deformation range should result in more complete characteristics of material properties, suitable for the foreseen applications. Similar effects can be expected after application of cold deformation after ageing. Practical implications: The elaborated research results present some utilitarian qualities since they can be used in development of process conditions for industrial scale production of strips from CuTi4 alloy of defined properties and operating qualities. Originality/value: The mentioned factors influence the mechanism and kinetics of precipitation and subsequently the produced wide ranges of functional properties of the Cu-Ti alloys.

2

Influence of cold working on microstructure and properties of annealing CuTi4 alloy

Konieczny J., Rdzawski Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 55, nr 2

331--338

EN

Purpose: The aim of this study was to investigate the effect of cold plastic deformation of the supersaturation on the structure and properties of the CuTi4 alloy after aging. Design/methodology/approach: CuTi4 alloy of supersaturation temperature of 900°C after heating for 1 hour. After solutioning alloy was processed in two ways: first aged in the temperature range 450-600°C and the second stage rolling reduction with Z=50%, and then aged in the temperature range 450-600°C. Findings: The results confirmed that the temperature within the range 500-600°C, the hardness increases with increasing aging time until reaching the maximum, but then with increasing aging time the hardness decreases. By using methods of electron microscopy (SEM, EDS, EBSD, TEM) after aging at 550°C after 1 minute of modulated microstructure was observed - characteristic for the spinodal transformation and lamellar, formed by nucleation and growth. Research limitations/implications: A widely used method for increasing the strength properties of metal alloys, in addition to cold plastic deformation, is the strengthening of new phases separated particles during aging. The effect of cold rolling operation between solutioning and aging on microstructure and properties of alloyed copper CuTi4. Further examination also included the effect of time and aging temperature. Practical implications: On the basis of conductivity, the influence of cold plastic deformation and subsequent aging on the hardness and electrical conductivity of the alloy CuTi4. It was found that with increasing aging time and with increasing aging temperature increases electrical conductivity of the alloy. On the basis of X-rays can be concluded that in alloyed copper containing 4% Ti and precipitation hardening metastable phase β’-Cu4Ti is separated, which occurs both in the previously deformed and undeformed cold worked alloy.

3

Antibacterial properties of copper and its alloys

Konieczny J., Rdzawski Z.

Archives of Materials Science and Engineering

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2012

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Vol. 56, nr 2

53--60

EN

Purpose: The goal of the work is analysis of the knowledge extent on the bactericidal activity of copper and its alloys. Design/methodology/approach: Analysis of publications on the antibacterial properties of copper in the engineering and medical journals, taking also into account publications on the earliest documented employment of copper as the bactericide or medicine. Findings: Analysis of the investigation results presented in more than 350 scientific publications and reports worked out under commission from the Ministry of Health, including 312 scientific publications from the years 1892-1973, indicate to the antimicrobial action of copper and its alloys, which killing bacteria and viruses slows down growth of the microorganisms, and especially of: cobacillus, Legionella pneumophila, Salmonella, Staphylococcus aureus, poliovirus. Research limitations/implications: Application of the acquired research results in hospitals, outpatients’ clinics, and other public medical centres, will make it possible to reduce morbidity resulting from infections, especially of patients after serious medical treatment, operations, or after the complex antibiotic cure which has led them to decline of immunity. Practical implications: Reduction of health care costs is possible in every country by implementation of the acquired investigation results, as a consequence of the decreased treatment costs, by shortening the patients’ stay in a hospital. According to the assessment of the Department of Health of the United Kingdom these savings total to 1 billion pounds a year. Originality/value: Implementation of the analysis of results of investigations on the bactericidal activity of copper and copper based alloys will add to the increase of the patients’ safety level in the public medical centres.

4

Misorientation in rolled CuTi4 alloy

Konieczny J., Rdzawski Z.

Archives of Materials Science and Engineering

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2011

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Vol. 52, nr 1

5-12

EN

Purpose: The aim of the work is to investigate the microstructure heat treated and cold rolled commercial copper alloy CuTi4. Design/methodology/approach: The Investigations of the structure were made on ZEISS SUPRA 25 with EBSD method. Observations of the structure on thin foils were made on the JOEL 3010 transmission electron microscope (TEM). Findings: Decomposition of supersaturated solid solution in that alloy is similar to the alloys produced in laboratory scale. The observed differences in microstructure after supersaturation were related to the presence of undissolved Ti particles and increased segregation of titanium distribution in copper matrix including microareas of individual grains. The mentioned factors influence the mechanism and kinetics of precipitation and subsequently the produced wide ranges of functional properties of the alloy. Research limitations/implications: Cold deformation (50% reduction) of the alloy after supersaturation changes the mechanism and kinetics of precipitation and provides possibilities for production of broader sets of functional properties. It is expected that widening of the cold deformation range should result in more complete characteristics of material properties, suitable for the foreseen applications. Similar effects can be expected after application of cold deformation after ageing. Practical implications: The elaborated research results present some utilitarian qualities since they can be used in development of process conditions for industrial scale production of strips from CuTi4 alloy of defined properties and operating qualities. Originality/value: The mentioned factors influence the mechanism and kinetics of precipitation and subsequently the produced wide ranges of functional properties of the Cu-Ti alloys.