Influence of plastic deformation on the change of electrical and mechanical properties oxygen-free (OF) copper and copper alloy wires

This article is devoted to the comparison of changes in mechanical and electrical properties due to the applied deformation of copper and copper alloy rods. Bars from four different production technologies were deformed in the drawing process, including oxygen-free (OF) copper, electrolytic copper ETP, copper from cable granulate and silver copper with a high silver content up to 15 wt. % obtained in laboratory technology. The article presents the chemical purity, physical and electrical properties of rods before deformation. The summary of the research on the selected materials are changes in mechanical properties and electrical conductivity as a function of deformation up to 3,5 on a logarithmic scale and the coefficient of electromechanical efficiency WEM

Characterisation of Cu-CNTs composite electrical properties in elevated temperatures

The current trend towards nanotechnology creates possibilities for its use in materials science as manufacturing material with extraordinary properties, and is one of the goals for scientists in this field. Carbon nanotubes in particular are promising due to their electrical, thermal and mechanical properties, which have been of interest for researchers around the world. This paper focuses on the manufacturing process of the Cu-CNT composite via powder metallurgy and KOBO extrusion process, its further cold drawing process, and electrical resistance test at an elevated temperature. As obtained data proved, the higher the CNT content the lower the electrical resistance

Calcium Homeostasis in Myogenic Differentiation Factor 1 (MyoD)-Transformed, Virally-Transduced, Skin-Derived Equine Myotubes

Dysfunctional skeletal muscle calcium homeostasis plays a central role in the pathophysiology of several human and animal skeletal muscle disorders, in particular, genetic disorders associated with ryanodine receptor 1 (RYR1) mutations, such as malignant hyperthermia, central core disease, multiminicore disease and certain centronuclear myopathies. In addition, aberrant skeletal muscle calcium handling is believed to play a pivotal role in the highly prevalent disorder of Thoroughbred racehorses, known as Recurrent Exertional Rhabdomyolysis. Traditionally, such defects were studied in human and equine subjects by examining the contractile responses of biopsied muscle strips exposed to caffeine, a potent RYR1 agonist. However, this test is not widely available and, due to its invasive nature, is potentially less suitable for valuable animals in training or in the human paediatric setting. Furthermore, increasingly, RYR1 gene polymorphisms (of unknown pathogenicity and significance) are being identified through next generation sequencing projects. Consequently, we have investigated a less invasive test that can be used to study calcium homeostasis in cultured, skin-derived fibroblasts that are converted to the muscle lineage by viral transduction with a MyoD (myogenic differentiation 1) transgene. Similar models have been utilised to examine calcium homeostasis in human patient cells, however, to date, there has been no detailed assessment of the cells’ calcium homeostasis, and in particular, the responses to agonists and antagonists of RYR1. Here we describe experiments conducted to assess calcium handling of the cells and examine responses to treatment with dantrolene, a drug commonly used for prophylaxis of recurrent exertional rhabdomyolysis in horses and malignant hyperthermia in humans

Influence of plastic deformation on the change of electrical and mechanical properties oxygen-free (OF) copper and copper alloy wires

This article is devoted to the comparison of changes in mechanical and electrical properties due to the applied deformation of copper and copper alloy rods. Bars from four different production technologies were deformed in the drawing process, including oxygen-free (OF) copper, electrolytic copper ETP, copper from cable granulate and silver copper with a high silver content up to 15 wt. % obtained in laboratory technology. The article presents the chemical purity, physical and electrical properties of rods before deformation. The summary of the research on the selected materials are changes in mechanical properties and electrical conductivity as a function of deformation up to 3,5 on a logarithmic scale and the coefficient of electromechanical efficiency WEM

Characterisation of Cu-CNTs composite electrical properties in elevated temperatures

The current trend towards nanotechnology creates possibilities for its use in materials science as manufacturing material with extraordinary properties, and is one of the goals for scientists in this field. Carbon nanotubes in particular are promising due to their electrical, thermal and mechanical properties, which have been of interest for researchers around the world. This paper focuses on the manufacturing process of the Cu-CNT composite via powder metallurgy and KOBO extrusion process, its further cold drawing process, and electrical resistance test at an elevated temperature. As obtained data proved, the higher the CNT content the lower the electrical resistance

Otrzymywanie oraz własności i mikrostruktura wysokowytrzymałych i wysoko przewodzących drutów ze stopów Cu-Ag

Research results of manufacturing composite filamentary nanostructure Cu-Ag alloys with silver addition from 5 to 15% wt. are presented in the paper. Manufacturing technology of these composites and variable solubility of silver in copper and copper in silver in the range of solid solutions. Suitable quantity and processing sequences of high deformation plastic working and heat treatment allows to obtain wires constituted from Cu and Ag fibres with nanometric transverse dimensions and in consequence provide to optimum superposition of high mechanical strength, high electrical conductivity and sufficient ductility of Cu-Ag alloys. The paper presents the method of continuous casting of alloys, selected physico-chemical properties and degree of deformation. Influence of chosen heat treatment method over electrical and mechanical properties of both casts and micro wires on mechanical and electrical properties of cast materials during converting them into micro wires with tensile strength higher than 1200 MPa and electrical conductivity higher than 40 MS/m are presented too. Research results of optical and scanning microscopy structure analysis were presented for casts and wires submitted to various thermo-mechanical strengthening.Praca dotyczy badań nad kształtowaniem zespołu bardzo wysokich własności wytrzymałościowych i elektrycznych drutów i mikro-drutów ze stopów CuAg5 i CuAg15. Technologia wytwarzania drutów ze stopów Cu-Ag wykorzystuje zjawisko obustronnej zmiennej rozpuszczalności składników stopów w stanie stałym. Jak wykazały przeprowadzone badania, odpowiednie połączenie przeróbki plastycznej materiałów o strukturze odlewniczej z międzyoperacyjna obróbka cieplna umożliwia uzyskanie korzystnej kompozytowej mikrostruktury silnie wydłużonych włókien Cu i Ag o nanometrycznych wymiarach poprzecznych. Optymalizacja parametrów technologicznych pozwala na uzyskanie drutów i mikro-drutów Cu-Ag o wytrzymałości na rozciąganie w zakresie 100÷ 1300 MPa przy równocześnie wysokiej przewodności elektrycznej wynoszącej 70 ÷85% w skali IACS. W artykule pokazano metodę uzyskania stopów Cu-Ag oraz wyniki badan wybranych własności fizykochemicznych, schemat odkształcenia oraz badania wpływu wstępnej obróbki cieplnej materiałów w stanie odlanym na zmianę własności elektrycznych i mechanicznych zarówno odlewów jak i drutów po przeróbce plastycznej. Zamieszczono także wyniki obserwacji strukturalnych przy zastosowaniu mikroskopii optycznej i skaningowej odlewów oraz ewolucje struktury po przeróbce plastycznej oraz po różnych etapach międzyoperacyjnej obróbki cieplnej

Research And Characterization Of Cu – Graphene, Cu-CNT’s Composites Obtained By Mechanical Synthesis

Currently we can observe a worldwide trend to find new materials with extraordinary properties. In particular these researches are aimed to find a method to improve electrical conductivity, mechanical properties, corrosion resistance and rheological behavior of known materials. This effect can be achieved by a synthesis of modern carbon materials with metals. In this paper authors presented research results of synthesis process for Cu-graphene and Cu-CNT’s composites obtained by the mechanical synthesis in cold drawing process. The article presents also the results of electrical conductivity measurements and structural analysis of carbon particles presence in copper matrix. The research has shown that obtained composites have electrical conductivity lower than used copper base material. Additionally, the structural analysis has shown that after the drawing process carbon materials particles are mechanically pressed into Cu in the matrix, and these particles do not participate in the current flow, creating an actual barrier for electrons transport

New Al-Ag Alloys for Electrical Conductors with Increased Current Carrying Capacity

The paper shows a new idea of aluminium alloys. New alloys with specially selected alloying element i.e. silver have electrical conductivity similar to pure aluminium at ambient temperature and better than pure aluminium electrical conductivity at increased temperatures. Al-Ag alloys for electrical applications (mainly for electrical conductors) due to high electrical conductivity at increased temperatures at the level of the maximum conductor working temperatures give possibility of better current capacity of conductors. The experimental results of basic mechanical properties and the electric conductivity versus temperature relation are shown in the paper as well as examples of the tested material operational properties. The summary gives theoretical analysis based on examples of the potential applications of Al-Ag alloys (new conductor designs) which provide the benefits of the new solutions in comparison to traditional conductors

New Al-Ag Alloys for Electrical Conductors with Increased Current Carrying Capacity

The paper shows a new idea of aluminium alloys. New alloys with specially selected alloying element i.e. silver have electrical conductivity similar to pure aluminium at ambient temperature and better than pure aluminium electrical conductivity at increased temperatures. Al-Ag alloys for electrical applications (mainly for electrical conductors) due to high electrical conductivity at increased temperatures at the level of the maximum conductor working temperatures give possibility of better current capacity of conductors. The experimental results of basic mechanical properties and the electric conductivity versus temperature relation are shown in the paper as well as examples of the tested material operational properties. The summary gives theoretical analysis based on examples of the potential applications of Al-Ag alloys (new conductor designs) which provide the benefits of the new solutions in comparison to traditional conductors

Badania i charakteryzacja kompozytów Cu – grafen, Cu-CNT’s uzyskiwanych metodą syntezy mechanicznej

Currently we can observe a worldwide trend to find new materials with extraordinary properties. In particular these researches are aimed to find a method to improve electrical conductivity, mechanical properties, corrosion resistance and rheological behavior of known materials. This effect can be achieved by a synthesis of modern carbon materials with metals. In this paper authors presented research results of synthesis process for Cu-graphene and Cu-CNT’s composites obtained by the mechanical synthesis in cold drawing process. The article presents also the results of electrical conductivity measurements and structural analysis of carbon particles presence in copper matrix. The research has shown that obtained composites have electrical conductivity lower than used copper base material. Additionally, the structural analysis has shown that after the drawing process carbon materials particles are mechanically pressed into Cu in the matrix, and these particles do not participate in the current flow, creating an actual barrier for electrons transport.Aktualnie na świecie poszukuje się nowych materiałów o własnościach dotychczas nieosiągalnych. Poszukiwania te głównie ukierunkowane są na podwyższenie przewodności elektrycznej, własności wytrzymałościowych, odporności korozyjnej, reologicznej itd. Efekt ten może być osiągnięty przez łączenie nowoczesnych nanomateriałów węglowych z metalami. W artykule przedstawiono wyniki badań syntezy miedzi z grafenem i nanorurkami metodą syntezy mechanicznej w procesie ciągnienia uzyskanych materiałów gradientowych Cu-grafen oraz Cu-CNT’s. W artykule zamieszczone zostały wyniki badań przewodności elektrycznej właściwej oraz wyniki analiz strukturalnych obecności cząstek materiałów węglowych w osnowie miedzianej. Przeprowadzone badania wykazały, że uzyskane kompozyty posiadają obniżoną przewodność elektryczną w stosunku do osnowy miedzianej. Ponadto badania strukturalne wykazały, że w osnowie po procesie ciągnienia występują wprasowane w Cu cząstki materiałów węglowych, które nie biorą udziału w przewodzeniu prądu stanowiąc barierę w transporcie elektronów