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2011
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tom R. 56, nr 5
272-278
PL
W celu polepszenia własności warstwy wierzchniej przeprowadzono powierzchniowe stopowanie magnezu za pomocą lasera, stosując jako metal stopujący aluminium. W wyniku badań stwierdzono, że na mikrostrukturę stopowanej warstwy magnezu wpływają zarówno parametry pracy lasera, jak i grubość warstwy aluminium przeznaczonego do stopowania, którym pokryto powierzchnię magnezu przed obróbką laserową. Ze względu na mikrostrukturę w stopowanej warstwie wyróżnić można trzy obszary: obszar zawierający eutektykę utworzoną przez Mg17Al12 i roztwór stały aluminium w magnezie, obszar jednofazowy w którym zidentyfikowano związek międzymetaliczny Mg17Al12 oraz obszar, o strukturze roztworu stałego aluminium w magnezie. Stwierdzono również, że grubość stopowanej warstwy i jej mikrostruktura nie są stałe na długości warstwy, gdyż zdolność absorpcji ciepła przez stopowaną próbkę rośnie w sposób ciągły. Twardość stopowanej warstwy wierzchniej, zależna od jej mikrostruktury, zawierała się w zakresie od 50 do 296 HV0,1.
EN
To improve properties of the surface layer of magnesium, laser surface alloying with aluminium was performed. It was shown that the microstructure in the laser alloyed magnesium layer depends on the treatment parameters and the thickness of aluminium layer that was deposited on the magnesium surface before the laser action. In the laser melted zone three areas with respect to microstructure were defined: area containing eutectic composed of Mg17Al12 and solid solution of aluminium in magnesium, single?phase region with Mg17Al12 intermetallic compound and single?phase region of solid solution of aluminium in magnesium. It was also found that the thickness of alloyed layers and its microstructure are not constant on the layer´s length because the absorbtion heat resulted in an increase of the temperature. Hardness of the alloyed surface layer depending on its microstructure was within the range from 50 to 296 HV0.1.
EN
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.
3
Content available remote Effect of laser alloying on wear properties of Ti-6Al-4V surface layer
84%
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2007
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tom Vol. 31, nr 3
63-69
EN
Titanium alloys are characterised by a poor wear resistance when interacting with other construction materials, and by a great tendency to become scuffed. Laser alloyed surface layers, due to forming hard ceramic particles spaced in ductile matrix, have a lower wear intensity as compared to conventional alloys and enables application of titanium alloys as a part of tribological couple. The aim of this paper was examination of microstructure and wear properties of the surface layer Ti-6Al-4V titanium alloy remelted by CO2 laser using pre-placed SiC layer.
PL
Stopy tytanu charakteryzują się małą odpornością na ścieranie przy współpracy w parach konstrukcyjnych oraz wykazują skłonność do zacierania. Laserowe stopowanie umożliwia wytworzenie warstwy wierzchniej o budowie kompozytowej złożonej z twardych cząsteczek faz rozmieszczonych w plastycznej osnowie. Prowadzone badania wykazały, że stopowanie laserowe powoduje znaczne zmniejszenie zużycia ściernego w porównaniu do konwencjonalnych stopów tytanu i umożliwia rozszerzenie ich zastosowania w parach tribologicznych. W pracy przedstawiono wyniki badań mikrostruktury i właściwości tribologicznych warstwy wierzchniej stopu tytanu Ti-6Al-4V po stopowaniu proszkiem SiC.
PL
W pracy przedstawiono wyniki badań struktury oraz twardości stali narzędziowej do pracy na gorąco 32CrMoV12-28 stopowanej węglikiem wolframu oraz tytanu. Badania przeprowadzono przy użyciu nowoczesnego lasera dużej mocy HPDL. Stwierdzono zmiany struktury polegające na jej rozdrobnieniu, a także wzrost twardości w porównaniu do stali nie obrobionej laserowo. Określono wpływ parametrów obróbki laserowej na strukturę i twardość materiału.
EN
The laser treatment as a part of the new generation techniques applied in metal surface technology is discussed in this paper. Laser treatment is presented with remelting of hot work tool steel 32CrMoV12-28 with ceramic powders, especially TiC Titanium Carbide and WC Tungsten Carbide. The structure investigation, and improvement of mechanical properties, is the practical aim of this work, as well as improvement of hardness as a very important property for practical use.
5
Content available remote Struktura stali łożyskowej po borowaniu laserowym
84%
PL
W artykule dokonano oceny struktury stali łożyskowej po borowaniu laserowym w porównaniu ze strukturą po borowaniu dyfuzyjnym. W szczególności analizowano strukturę granicy strefy przetopionej i stwierdzono, że stanowią ją częściowo przetopione ziarna martenzytu. Ponadto obserwowano równomierne stężenie boru w strefie naborowanej, którą tworzy przede wszystkim borek żelaza Fe(2)B. W badaniach stosowano metodę spektroskopii elektronów Augera (AES) i mikroanalizę rentgenowską.
EN
In this paper laser and diffusion boronizing structural effects on bearing steel have been compared. Structure at the border between melted and hardened zones structure has been analyzed particularly. At this border partly melted martensite grains have been observed. Moreover, steady boron distribution has been found in melted zone, which consist mainly of Fe2B iron borides. In this research Auger Electron Spectroscopy (AES) and X-ray microanalysis methods have been applied.
PL
W artykule omówiono strukturę i mikrotwardość azotowanej stali 42CrMo4 po stopowaniu laserowym borem. Proces wytwarzania warstwy wierzchniej składał się z dwóch etapów: azotowania gazowego oraz stopowania laserowego borem. Zbadano wpływ obróbki laserowej na mikrostrukturę i mikrotwardość wytworzonej warstwy wierzchniej. Badano ścieżki ułożone wzdłuż linii prostej i śrubowej. Mikrostruktura ścieżek wykazała występowanie trzech stref: przetopionej, wpływu ciepła i rdzenia. Zaobserwowano, że ze wzrostem mocy lasera wzrasta twardość ścieżek, ale zwiększa się przy tym porowatość struktury.
EN
The paper presents structure and microhardness of nirrided 42CrMo4 steel after laser alloying with boron. Surface layer making process consisted of two stages, gaseous nitriding and laser alloying with boron. The purpose of this experiment was to test the effect of laser treatment parameters on surface layer microstructure and microhardness. Tests were carried out on straight line tracks and helical line tracks. Microstructure of tracks shows the presence of three zones: melted zone, heat affected zone and core. It was observed, that together with gradual increase of laser power, microhardness of trucks increased, as well as its porosity.
7
Content available remote Laser surface treatment of magnesium alloy with WC and TiC powders using HPDL
84%
EN
Purpose: The aim of this work was to improve the surface layer cast magnesium alloy EN-MCMgAl6Zn1 by laser surface treatment. The purpose of this work was also to determine the laser treatment parameter. Design/methodology/approach: The laser treatment of an EN-MCMgAl6Zn1 magnesium alloy with alloying WC and also TiC powders was carried out using a high power diode laser (HPDL). The resulting microstructure in the modified surface layer was examinated using scanning electron microscopy. Phase composition was determined by the X-ray diffraction method using the XPert device. The measurements of microhardness of the modified surface layer was also studied. Findings: The alloyed region has a fine microstructure with hard carbide particles. Microhardness of laser surface alloyed layer with both TiC and WC particles was significantly improved as compared to alloy without laser treatment. Research limitations/implications: In this research two powders (WC and TiC) were used with the particle size over 5 µm This investigation presents different speed rates feed by one process laser power. Practical implications: The results obtained in this investigation were promising to compared other conventional processes. High Power Diode Laser can be used as an economical substitute of Nd:YAG and CO2 to improve the surface magnesium alloy by feeding the carbide particles. Originality/value: The originality of this work is applying of High Power Diode Laser for alloying of magnesium alloy using hard particles like tungsten carbide and titanium carbide.
8
Content available remote Characteristic of Mg-Al-Zn alloys after laser treatment
84%
EN
Purpose: The structure and the properties of casting magnesium alloy EN-MCMgAl3Zn1, EN-MCMgAl6Zn1, EN-MCMgAl9Zn1 and EN-MCMgAl12Zn1 after laser surface treatment are presented in this paper. The aim of this work was to improve the surface layer cast magnesium Mg-Al-Zn by melting and feeding of TiC particle on the surface. The purpose of this work was to determine the laser treatment parameter. Design/methodology/approach: The experiments were performed using high power diode laser. The laser treatment of an EN-MCMgAl3Zn1, EN-MCMgAl6Zn1, EN-MCMgAl9Zn1, EN-MCMgAl12Zn1 magnesium alloy with alloying TiC powders was carried out using a high power diode laser (HPDL). The resulting microstructure in the modified surface layer was examinated using scanning electron microscopy. Phase composition was determined by the X-ray diffraction method using the XPert device. The measurements of hardness of the modified surface layer was also studied. Findings: The alloyed region has a fine microstructure with hard carbide particles. Hardness of laser surface alloyed layer with TiC particles was significantly improved as compared to alloy without laser treatment for EN-MCMgAl3Zn1 and EN-MCMgAl6Zn1 alloys. Research limitations/implications: In this research one powder - TiC was used with the particle size over 6 µm. This investigation presents different speed rates feed and different laser power value for four type of magnesium alloys. Practical implications: The results obtained in this investigation were promising compared to other conventional processes. High Power Diode Laser can be used as an economical substitute of Nd:YAG and CO2 to improve the surface magnesium alloy by feeding the carbide particles. Originality/value: The originality of this work is applying of High Power Diode Laser for alloying of magnesium alloy using titanium carbide.
10
67%
EN
Purpose: The paper presents investigation results of the structure and properties of alloying surface layer of the X40CrMoV5-1 hot work tool steel, using the high power diode laser HPDL. Tantalum and vanadium carbides powders were used for alloying and the X40CrMoV5-1 conventionally heat treated steel was used as reference material. Design/methodology/approach: Metallographic examinations of the material structures after laser alloying surface layer were made on light microscope and transmission electron microscope. The resistance research has been done with the use of the pin-on-disc method. Hardness tests were made with Rockwell method in C scale. Findings: It was found out in examinations of the surface layer that it can be possible to obtain high quality top layer with better properties compared to material after a standard heat treatment. Research limitations/implications: In this research two powders (TaC and VC) were used for alloying of the surface layer of investigated steel. Practical implications: The structure as well as improvement of mechanical properties is a practical aim of this work as well as improvement of hardness as a very important properties for practical use. Originality/value: The research results of this type of heat treatment show that there is a possibility of applying the worked out technology to manufacturing or regeneration of chosen hot working tools.
11
Content available remote Structure changes and mechanical properties of laser alloyed magnesium cast alloys
67%
EN
Purpose: The aim of this work was to investigate structure and mechanical properties of the MCMgAl12Zn1 casting magnesium alloys after laser treatment. The laser treatment was carried out using a high power diode laser (HPDL). Design/methodology/approach: The laser processing of TiC, WC, SiC particles in MCMgAl12Zn1 and the resulted microstructures and properties are discussed in this paper. The resulting microstructure in the modified surface layer was examined. Phase composition was determined by the X-ray diffraction method using XPert device. The measurements of hardness after laser melt injection was also studied. Findings: Structure of the solidyifying material after laser alloying is characteristic with occurrences of areas with the diversified morphology, dependent on solidification rate of the magnesium alloys, is characteristic of structure of the solidified material after laser alloying. The MCMgAl12Zn1 casting magnesium alloys after laser alloying demonstrate similar hardness tests results, in reference to hardness of the alloys before their laser treatment. Research limitations/implications: In this research three powders (titanium carbide, tungsten carbide and silicon carbide) were used to reinforcing the surface of the MCMgAl12Zn1 casting magnesium alloys. Practical implications: High power diode laser can be used as an economical substitute for CO₂ and Nd:YAG lasers to modify the surface magnesium alloy by feeding the carbide particles. Originality/value: The originality of this work is applying of High Power Diode Laser for laser treatment of cast magnesium alloy consisting in fusion penetration of the hard particles of titanium, tungsten, and silicon carbides into the remelted surface layer of the alloy.
12
67%
PL
Opisano podstawy procesów laserowych spawania, lutowania miękkiego i twardego, napawania, wprowadzania pierwiastków stopowych i obróbki cieplnej oraz przeprowadzono analizę zalet i ograniczeń poszczególnych procesów. Przedstawiono wyniki badań doświadczalnych i przemysłowych nad zastosowaniem lasera HPDL ROFIN DL 020 do spawania złączy cienkich blach z różnych materiałów konstrukcyjnych, lutowania miękkiego i twardego miedzi, napawania narzędzi kuźniczych i zaworów, stopowania blachy ze stopu tytanu i płytki ze stopu magnezu, obróbki cieplnej matryc i stempli oraz przetapiania wad powierzchniowych łopatki turbiny z nadstopu niklu.
EN
It has been described the principles of laser processes of welding , brazing, soldering, weld surfacing, alloying and heat treatment as well as it has been analysed the advantages and shortcomings of particular processes. The results of laboratory and industrial testing of application possibility of high power diode laser ROFIN DL 020 for welding of different construction material sheets, brazing and soldering of copper, building up of forging tools and valves, alloying of titanium alloy sheets and magnesium alloy plates, heat treatment of die blocks and punches as well as for remelting of surface defects in nickel superalloy turbine blades have been presented.
PL
Przedstawiono wyniki badań wpływu warunków technologicznych i parametrów przetapiania laserowego lub stopowania laserowego węglikami NbC i TiC na strukturę i własności warstwy wierzchniej stali stopowej narzędziowej do pracy na gorąco X40CrMoV5-1. Próby przetapiania i stopowania laserowego wykonano za pomocą lasera diodowego dużej mocy (HPDL). Badania wykazują, że w zależności od rodzaju zastosowanych proszków węglików oraz mocy lasera (HPDL) możliwe jest kształtowanie struktury i własności warstwy wierzchniej badanej stali. Przetapianie laserowe warstwy wierzchniej badanej stali w atmosferze argonu bez wprowadzania dodatków stopujących do ciekłego jeziorka metalu w całym zakresie zastosowanej mocy lasera prowadzi do utworzenia drobnoziarnistej struktury dendrytycznej, o kierunku krystalizacji zgodnym z kierunkiem odprowadzenia ciepła ze strefy oddziaływania wiązki lasera. W wyniku przetapiania laserowego lub stopowania laserowego następuje zmiana własności warstwy wierzchniej badanej stali, w porównaniu do analogicznych własności stali uzyskanych w wyniku konwencjonalnej obróbki cieplnej, która zależy od mocy lasera użytej do przetapiania lub stopowania laserowego. Wzrostowi twardości warstwy wierzchniej uzyskanej w wyniku przetapiania lub stopowania węglikami TiC lub NbC przy użyciu lasera HPDL towarzyszy wzrost własności trybologicznych w porównaniu do stali poddanej konwencjonalnej obróbce cieplnej.
EN
The results of remelting and alloying laser parameters on the structure and properties of the surface layer of the X40CrMoV5-1 hot work tool steels, using the high power diode laser (HPDL) are presented. Investigation indicate the influence of the alloying carbides on the structure and properties of the surface layer of investigated steel depending on the kind of alloying carbides and power implemented laser (HPDL). Laser alloying of surface layer of investigated steel without introducing alloying additions into liquid molten metal pool, in the whole range of used laser power, causes size reduction of dendritic microstructure with the direction of crystallization consistent with the direction of heat carrying away from the zone of impact of laser beam. Remelting of the steel without introducing into liquid molten pool the alloying additions in the form of carbide powders, causes slight increase of properties of surface layer of investigated steel in comparison to its analogical properties obtained through conventional heat treatment, depending on the laser beam power implemented for remelting. The increase of hardness of surface layer obtained throughout remelting and alloying with carbides by high power diode laser is accompanied by increase of tribological properties, when comparing to the steel processed with conventional heat treatment.
14
67%
EN
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.
PL
W artykule omówiono strukturę, mikrotwardość i odporność na zużycie przez tarcie azotowanej stali 42CrMo4 po laserowym stopowaniu borem. Badaniom poddano ścieżki ułożone wzdłuż linii śrubowej. Po laserowej obróbce w mikrostrukturze stwierdzono występowanie trzech stref: przetopionej, wpływu ciepła i rdzenia. Badania wykazały stopniowy spadek mikrotwardości od powierzchni do rdzenia. Odporność na zużycie przez tarcie warstw azotowanych, stopowanych borem zależy od parametrów laserowej obróbki cieplnej.
EN
The paper presents structure, microhardness and wear resistance of nitrided 42CrMo4 steel after laser alloying with boron. Tests were carried out with helical line tracks. In the microstructure after laser heat treatment three zones have been observed: melted zone, heat affected zone and core. Research proved gradual decresing of microhardness from surface to core. The wear resistance of laser surface modification layer dependent on laser treatment parameters.
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