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Search Results: 1 - 10 of 138809 matches for " K. Labisz "
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Transmission electron microscope studies of the chromium cast iron modified at use of B4C addition
A. Studnicki,K. Labisz,W. Ozgowicz
Archives of Foundry Engineering , 2010,
Abstract: Results of studies of the high alloy chromium cast iron with boron addition in form of the B4C phase powder are presented in this paper.The main field of interest is the identification of phases based on the transmission electron microscope study, occurred in this alloy aftersolidification process. The structure mainly consists of the austenite matrix and M7C3 carbide identified as the Cr7C3 phase.
HPDL Remelting of Anodised Al-Si-Cu Cast Alloys Surfaces
K. Labisz,T. Tański,D. Janicki
Archives of Foundry Engineering , 2012,
Abstract: The results of the investigations of the laser remelting of the AlSi9Cu4 cast aluminium alloy with the anodised and non-anodised surfacelayer and hardness changes have been presented in this paper. The surface layer of the tested aluminium samples was remelted with thelaser of a continuous work. The power density was from 8,17 103 W/cm2 to 1,63 104 W/cm2. The metallographic tests were conducted inform of light microscope investigations of the received surface layer. The main goal of the investigation was to find the relation betweenthe laser beam power and its power density falling on a material, evaluating the shape and geometry of the remelted layers and theirhardness. As the substrate material two types of surfaces of the casted AlSi9Cu4 alloy were applied – the non–treated as cast surface aswell the anodized surface. As a device for this type of surface laser treatment the High Power Diode Laser was applied with a maximumpower of 2.2 kW and the dimensions of the laser beam focus of 1.8 x 6.8 mm. By mind of such treatment it is also possible to increasehardness as well eliminate porosity and develop metallurgical bonding at the coating-substrate interface. Suitable operating conditions forHPDL laser treatment were finally determined, ranging from 1.0 to 2.0 kW. Under such conditions, taking into account the absorptionvalue, the effects of laser remelting on the surface shape and roughness were studied. The results show that surface roughness is reducedwith increasing laser power by the remelting process only for the non-anodised samples, and high porosity can be found in the with highpower remelted areas. The laser influence increases with the heat input of the laser processing as well with the anodisation of the surface,because of the absorption enhancement ensured through the obtained alumina layer.
Microstructure evaluation of long-term aged binary Ag-Cu alloy
K. Labisz,Z. Rdzawski,M. Pawlyta
Archives of Materials Science and Engineering , 2011,
Abstract: Purpose: In this work there are presented microstructure investigation results of the long aged Ag-Cu alloy used for monetary production. The purpose of this work was to determine the microstructural phase changes after 30 year ageing time, with appliance of transmission electron microscopy. Mainly the possibility of spinodal decomposition process occurrence was investigated.Design/methodology/approach: The investigations were performed using optical microscopy for the microstructure determination. By mind of the transmission and scanning electron microscopy the phase determination was possible to achieve. Morphology investigation of the Ag-Cu matrix and phase identification using electron diffraction, EBSD technique and SEM phase contrast methods was applied.Findings: After the long time ageing time and plastic deformation of the material there are morphological different areas of the Agα and Cuβ phase detected.Research limitations/implications: The investigated material samples were examined metallographically using light microscope, SEM, TEM with different image techniques. The hardness was measured using the Rockwell hardness tester, also EDS microanalysis and electron diffraction was performed.Practical implications: As an implication for practice use there is the possibility of application of long term ageing for mechanical properties improvement by natural ageing method. Also the comparison of microstructure change and deformation after long term ageing can deliver a new scientific view on the processes occurred in the microstructure over a long time period - spinodal decomposition can act as an example of this. Some other investigations should be performed in the future, but the knowledge found in this research shows an interesting investigation direction, where a low cost but long term treatment operations can be applied.Originality/value: The combination of TEM investigation for silver containing alloys makes the investigation very attractive for electronic, chemical and monetary industry branches.
Light and electron microscope investigations of cast Zn-Al alloys
B. Krupińska,Z. Rdzawski,K. Labisz
Archives of Materials Science and Engineering , 2012,
Abstract: Purpose: The aim of this work is to determine the influence of alloy modification on the crystallisation kinetics and microstructure of the cast zinc alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl8Cu1 alloy.Design/methodology/approach: approach The UMSA (Universal Metallurgical Simulator and Analyser) device allows it to determine the specific points of the solidifying alloy, including: Influence of the chemical concentrations of the modifiers, alloying additives, parameters of the melting process, influence of the cooling rate on the crystallization of phases and eutectics of the investigated alloys. Cooling rate influences the microstructure and properties of the investigated zinc cast alloys. For phase determination electron diffraction investigations were performed carried out on the transmission electron microscope.Findings: Change of the crystallization kinetics allows it to produce materials with improved properties, which are obtained by: microstructure refinement, reduction or elimination of segregation.Research limitations/implications: The material was examined metallographically and analysed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy.Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters.Originality/value: Investigations concerning the development of optimal chemical composition and production method of zinc-aluminium alloys with selected rare earth metals with improved properties compared to elements made of alloys with appliance of traditional methods, will contribute to a better understanding of the mechanisms influencing the improvement of functional properties of the new.
Crystallisation kinetics of the Zn-Al alloys modified with lanthanum and cerium
B. Krupińska,Z. Rdzawski,K. Labisz
Journal of Achievements in Materials and Manufacturing Engineering , 2011,
Abstract: Purpose: The aim of the investigation is to determine the influence of modification on crystallisation kinetics on microstructure of the cast zinc alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl8Cu1 alloy.Design/methodology/approach: The UMSA device (Universal Metallurgical Simulator and Analyser) allows it to determine the characteristic points of the crystallised alloy including: determination of the influence of alloy modifiers, alloying additives, melting process parameters, cooling rate influence on phase and eutectics crystallisation of the investigated alloys. In was fund that cooling rate has an influence an microstructure and mechanical properties of the cast zinc alloys.Findings: Crystallisation kinetics change makes it possible to produce materials with improved properties, which are obtained by: microstructure refinement and decrease or elimination of the segregation phenomenon.Research limitations/implications: The material was examined metallographic and analysed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy.Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters.Originality/value: value Investigation concerning the elaboration of optimal chemical composition and production method of zinc-aluminium alloys modified with chosen rare earths metals with enhanced properties compared to elements performed from traditional alloys and production methods, makes it possible to achieve a better understanding of mechanisms influencing improvement of mechanical properties of the new developed alloys.
Structure, texture and chemical composition of coatings deposited by PVD techniques
L.A. Dobrzański,K. Lukaszkowicz,K. Labisz
Archives of Materials Science and Engineering , 2009,
Abstract: Purpose: The aim of the research is the investigation of the structure, texture and chemical composition of coatings deposited by PVD technique (reactive dc magnetron sputtering method) onto the substrate from the CuZn40Pb2 brass.Design/methodology/approach: Microstructure was characterised using optical metallography, scanning and transmission electron microscopy. Changes of the chemical composition of the coatings were examinations made on the glow discharge optical spectrometer (GDOS).Findings: The hard PVD coatings deposited by reactive dc magnetron sputtering method demonstrate structure composed of fine crystallites. In case of the monolayer coatings the columnar structure occurs. Examinations of the PVD coating textures reveal that in most cases they have the binary textures.Research limitations/implications: In order to evaluate with more detail the possibility of applying these coatings in tools, further investigations should be concentrated on the determination of the mechanical and tribological properties of the coatings.Originality/value: The paper contributes to better understanding and recognition the structure of thin coatings deposited by PVD techniques.
Structure of monolayer coatings deposited by PVD techniques
L.A. Dobrzański,K. Lukaszkowicz,K. Labisz
Journal of Achievements in Materials and Manufacturing Engineering , 2006,
Abstract: Purpose: The aim of the research is the investigation of the structure of coatings deposited by PVD technique(reactive magnetron sputtering method) onto the substrate from the CuZn40Pb2 brass.Design/methodology/approach: Microstructure was characterised using optical metallography, scanning andtransmission electron microscopy.Findings: The hard PVD coatings deposited by reactive magnetron sputtering method demonstrate structurecomposed of fine crystallites. In case of the monolayer coatings the columnar structure occurs. Examinations of thePVD coating textures reveal that in most cases they have the binary textures {111} and {100} or {110} and {311}.Research limitations/implications: In order to evaluate with more detail the possibility of applying thesecoatings in tools, further investigations should be concentrated on the determination of the mechanical andtribological properties of the coatings.Originality/value: The paper contributes to better understanding and recognition the structure of thin coatingsdeposited by PVD techniques.
The influence of laser modification on the structure and properties of the X40CrMoV5-1 and 32CrMoV12-28 hot work tool steels
L.A. Dobrza?ski,E. Jonda,K. Labisz
Archives of Materials Science and Engineering , 2010,
Abstract: Purpose: The aim of this paper was to study the laser treatment technique and parameters, particularly the laser power, to achieve a high value of layer properties like hardness and microhardness for protection of this hot work tool steel from losing their work stability and to make the tool surface more resistant for work. The purpose of this work was also to determine technological and technical conditions for remelting the surface layer with HPDL.Design/methodology/approach: This work presents the results of new laser treatment techniques applied in metal surface technology. There is presented laser treatment with remelting and/or alloying of X40CrMoV5-1 and 32CrMoV12-28 hot work tool steels with carbide powders as well as results of laser remelting influence on microstructure and properties of the surface, carried out using the high power diode laser (HPDL). Special attention was devoted to monitoring of the layer morphology of the investigated material and on the particle occurred.Findings: The layer is without cracks and defects as well as has a considerably higher hardness value compared to the non remelted material. The hardness value increases according to the laser power used so that the highest power applied gives to highest hardness value in the remelted layer.Research limitations/implications: The results present only four selected laser powers by one process speed rate. Also carbide powders were used for alloying with the particle size in a chosen range.Originality/value: The originality of this work is based on applying of High Power Diode Laser for improvement of steel mechanical properties.
Comparison of the abrasion wear resistance of the laser alloyed hot work tool steels
L.A. Dobrzański,E. Jonda,K. Labisz
Archives of Materials Science and Engineering , 2012,
Abstract: Purpose: The paper presents the comparison of the abrasion wear resistance of the laser alloyed hot work tool steels X40CrMoV5-1 and 32CrMoV12-28.Design/methodology/approach: The tribological wear relationships using pin-on-disc test were specified for surface layers subject to laser treatment, determining the friction coefficient, and mass loss of the investigated surfaces.Findings: The performed investigations leads to the conclusions that for both types of steels - X40CrMoV5-1 and 32CrMoV12-28 the wear resistance measured using pin-on-disc, wear resistance test in the metal – metal arrangement, and wear resistance test in the metal – ceramic material arrangement, the wear resistance increases together with the hardness of the surface layer. This relationship is valid for all types of ceramic powders used. It is characteristic for the obtained surface layers, that the high roughness, multiple pores, irregularity, and flashes at the borders increases also together with the increasing of the laser power.Research limitations/implications: In order to evaluate with more detail the possibility of applying these surface layers in tools, further investigations should be concentrated on the determination of the thermal fatigue resistance of the layers.Practical implications: The alloyed layers which were formed on the surface of the hot work steels have shown significant improvement concerning properties. Good properties of the laser treatment make these layers suitable for various technical and industrial applications.Originality/value: A modification of tool steels surface using a laser beam radiation, as well as coating them with special pastes containing carbide particles allows the essential improvement of the surface layer properties - their quality and abrasion resistance, decreasing at the same time the surface quality, what is dependent on the processing parameters such as energy of impulse and the time of its work.
Anodization of cast aluminium alloys produced by different casting methods
K. Labisz,L.A. Dobrzański,J. Konieczny
Archives of Foundry Engineering , 2008,
Abstract: In this paper the usability of two casting methods, of sand and high pressure cast for the anodization of AlSi12 and AlSi9Cu3 aluminium cast alloys was investigated. With defined anodization parameters like electrolyte composition and temperature, current type and value a anodic alumina surface layer was produced. The quality, size and properties of the anodic layer was investigated after the anodization of the chosen aluminium cast alloys. The Alumina layer was observed used light microscope, also the mechanical properties were measured as well the abrasive wear test was made with using ABR-8251 equipment. The researches included analyze of the influence of chemical composition, geometry and roughness of anodic layer obtained on aluminum casts. Conducted investigations shows the areas of later researches, especially in the direction of the possible, next optimization anodization process of aluminum casting alloys, for example in the range of raising resistance on corrosion to achieve a suitable anodic surface layer on elements for increasing applications in the aggressive environment for example as materials on working building constructions, elements in electronics and construction parts in air and automotive industry.
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