Wyniki wyszukiwania - BazTech

1

Laser welding of stainless steel

Kurc-Lisiecka A., Lisiecki A.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 98, nr 1

32--40

EN

Purpose: of this paper was to analyze the influence of the basic parameters of laser welding (i.e. laser beam power and welding speed, as well as energy input) of butt joints of the 2.0 mm thick stainless steel AISI 304 sheets on the weld shape and joint quality. Design/methodology/approach: The preliminary trials of simulated laser welding by melting the austenitic stainless steel sheets (the so called bead-on-plate welding), as well as the welding of the test butt joints, were carried out using the high-power diode laser (HPDL) ROFIN DL 020, without the additional material (the technique of autogenous welding). A crucial parameter that determines both the mechanical properties and the corrosive resistance of a joint (the region of a weld and HAZ - heat affected zone) in the case of stainless steels with austenitic structure is energy input, which should be kept at a minimum, and at the same time full penetration and a proper shape of the fusion zone should be ensured. The investigations included the macrostructure and microstructure observations by light microscopy, researches of mechanical properties in a static tensile test and also microhardness measurements made by Vickers method. Findings: The results have shown that it is possible to provide a proper shape of the weld of fine-grained structure and narrow heat affected zone, but it requires careful selection of the welding parameters, especially a low energy input. The microhardness measurements showed that the in case of welding the butt joints using the high-power diode laser in HAZ area a slight increase in microhardness to approx. 185HV0.2 compared to base material (160-169HV0.2) and a decrease in microhardness in the fusion zone (FZ) to approx. 140- 150HV0.2 have been observed. All welded sample broke from the joint during the testing at tensile stress between 585 MPa and 605 MPa with corresponding percentage elongation in the range of 45-57%. It can be found that the joints strength is not less than the strength of the base metal of 2.0 mm thick AISI 304 austenitic stainless steel sheet. Research limitations/implications: Studies of the weldability of stainless steels indicate that the basic influence on the quality of welded joints and reduction of thermal distortions has the heat input of welding, moreover the highest quality of welded joints of austenitic stainless steel sheets are ensured only by laser welding. Practical implications: The laser welding technology can be directly applied for welding of austenitic steel AISI 304 sheets 2.0 mm thick. Originality/value: Application of high power diode laser for welding of austenitic stainless steel AISI 304.

2

Napawanie laserowe tarcz zderzaków kolejowych brązem aluminiowym

Sitarz M., Kurc-Lisiecka A., Gamon W.

Stal, Metale & Nowe Technologie

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2017

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nr 9-10

80--84

PL

W artykule opisano wyniki badań procesu napawania laserowego powierzchni tarcz zderzaków kolejowych ze stali S355J2 proszkiem na bazie brązu aluminiowego. Próby napawania wykonano za pomocą lasera diodowego dużej mocy (HPDL) LDF 4000-30 firmy LaserLine o mocy maksymalnej 4,0 kW. Badania obejmowały również obserwacje metalograficzne wytworzonych warstw, badania ich odporności na zużycie ścierne i pomiary twardości. Stwierdzono, że w wyniku napawania laserowego tarcz zderzaków kolejowych ze stali S355J2 proszkiem brązu CuAl9Fe3 i laserem diodowym HPDL możliwe jest wykonanie wysokiej jakości napoin bez nieciągłości strukturalnych i o korzystnej, drobnoziarnistej strukturze dendrytycznej w obszarze napoiny. Wykazano również, że napawanie laserowe brązem aluminiowym zapewnia znaczący wzrost odporności na zużycie ścierne powierzchni czołowych tarcz zderzaków kolejowych i pozwala na wyeliminowanie konieczności okresowego ich smarowania.

EN

The paper presents the results of the study of the laser powder cladding of railway buffers heads made of the S355J2 steel by aluminium bronze-based powder. The high power diode laser (HPDL) LDF 4000-30, produced by LaserLine, with the maximum output power of 4.0 kW, was used for the cladding trials. The investigations included also the metallographic observations of the clad layers, wear behaviour and hardness measurements. It was found that it is possible to produce high-quality clad layers of the aluminium bronze CuAl9Fe3 on the steel substrate, without any internal imperfections, such as voids or structural discontinuities, and characterized by fine-grained dendritic structure in the fusion zone of the clad. It was also shown that the laser cladding of aluminium bronze provides a significant increase of wear resistance of buffer working surfaces and can also eliminate the need of periodical greasing of these surfaces.

3

A Study of Susceptibility and Evaluation of Causes of Cracks Formation in Braze-Weld Filler Metal in Lap Joints Aluminum – Carbon Steel Made with Use of CMT Method and High Power Diode Laser

Adamiak M., Wyględacz B., Czupryński A., Górka J.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 4

2113--2123

EN

In this article results of studies on cracks formation susceptibility in braze-welded joints of thin aluminum sheets and double-sided zinc galvanized steel sheets for car body parts made by laser brazing with high power diode laser ROFIN DL 020 and CMT MIG-brazing, with filler material in form of powder and wire accordingly, were presented. Optimal welding parameters were determined by visual acceptance criteria. On joints made with optimal parameters further examinations were carried. Results of macro- and microscopic metallographic examinations, structural roentgenography, EDS microanalysis and hardness tests were presented. Causes of brittle intermetallic Fe-Al phases formation in Al-matrix filler metal in dissimilar aluminum – zinc plated carbon steel joints were pointed.

4

Spawanie laserowe złączy doczołowych z austenitycznej stali nierdzewnej AISI 304

Kurc-Lisiecka A.

Stal, Metale & Nowe Technologie

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2016

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nr 11-12

40--44

PL

Przedmiotem badań była analiza wpływu podstawowych parametrów spawania laserowego (tj. mocy wiązki laserowej i prędkości spawania oraz energii liniowej spawania) złączy doczołowych blach ze stali nierdzewnej AISI 304 o grubości 2,0 mm na kształt i jakość złączy. Wstępne próby symulowanego spawania laserowego poprzez przetapianie blach ze stali austenitycznej (ang. bead-on-plate welding), jak i spawania właściwych złączy próbnych wykonano przy użyciu lasera diodowego dużej mocy firmy ROFIN DL 020, techniką bez materiału dodatkowego. Krytycznym parametrem decydującym zarówno o własnościach mechanicznych, ale również odporności korozyjnej złącza (obszar spoiny oraz SWC) w przypadku stali nierdzewnych o strukturze austenitycznej jest energia liniowa spawania, która powinna być ograniczona do minimum, przy zapewnieniu pełnego przetopienia blach oraz poprawnego kształtu spoiny. Badania wykazały, że możliwe jest wykonanie laserem diodowym złączy doczołowych blach ze stali AISI 304 o grubości 2,0 mm o poprawnym kształcie i wysokiej jakości.

EN

The subject of the study was to analyze the influence of the basic parameters of laser welding (i.e. laser beam power and welding speed, as well as energy input) of butt joints of the 2.0 mm thick stainless steel AISI 304 sheets on the weld shape and joint quality. The preliminary tri-als of simulated laser welding by melting the austenitic stainless steel sheets (the so called bead-on-plate welding), as well as the welding of the test butt joints, were carried out using the high-power diode laser (HPDL) ROFIN DL 020, without the additional material (the technique of autogenous welding). A crucial parameter that determines both the mechanical properties and the corrosive resistance of a joint (the region of a weld and HAZ) in the case of stainless steels with austenitic structure is energy input, which should be kept at a minimum, and at the same time full penetration and a proper shape of the fusion zone should be ensured. The study have shown that it is possible to produce high quality butt joints of the 2.0 mm thick austenitic stainless steel AISI 304 sheets by means of diode laser.

5

Przyczyny pęknięć lutospoin w złączach różnoimiennych typu aluminium - ocynkowana stal niestopowa

Czupryński A., Janicki D.

Przegląd Spawalnictwa

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2016

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R. 88, nr 5

43--48

PL

W artykule przedstawiono wyniki badań dotyczących przyczyn pękania lutospoin w różnoimiennych złączach zakładkowych wykonanych laserem diodowym dużej mocy ROFIN DL 020 z użyciem materiału dodatkowego w postaci proszku aluminium, na przykładzie łączenia cienkiej blachy aluminiowej z blachą stalową pokrytą elektrolitycznie powłoką cynkową. Przedstawiono wyniki badań metalograficznych makroskopowych i mikroskopowych. Wskazano na problemy oraz przedstawiono sugestie dotyczące technologii lutospawania laserowego materiałów znacznie różniących się własnościami fizycznymi i składem chemicznym.

EN

A study on cracking phenomena during laser braze welding of dissimilar lap joints between aluminum thin plate and galvanized low carbon sheet steel is described. The experiments were carried out using a high power diode laser Rofin DL020 and aluminum powder as filler metal. Macro and microstructure analysis of the joints were analysed. Issues and problems in laser braze welding of materials having different chemical composition and physical properties are presented.

6

Comparison of the abrasion wear resistance of the laser alloyed hot work tool steels

Dobrzański L., Jonda E., Labisz K.

Archives of Materials Science and Engineering

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2012

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Vol. 55, nr 2

85-92

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.

7

Technology of laser repair welding of nickel superalloy inner flaps of jet engine

Klimpel A., Rzeźnikiewicz A.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 47, nr 1

66--74

EN

Purpose: of this paper: work out laser welding repair technology of cracked MIG 29 jet engine inner flaps made of cast nickel superalloy ŻS-3DK(ЖС-3ДК, Russian designation). Design/methodology/approach: The study were based on the analysis of laser HPDL powder INCONEL 625 welding of nickel superalloy using wide range of welding parameters to provide highest quality repair welds. Findings: Study of automatic welding technologies GTA, PTA and laser HPDL has shown that just laser welding can provide high quality repair welds. In order to establish the properties of welded joints repair cracks in the inner flap HPDL laser, studied the hardness, mechanical properties and erosive wear resistance. Research limitations/implications: It was found that only laser HPDL welding can provide high quality repair welds. Practical implications: The technology can be applied for repair cracked MIG 29 jet engine inner flaps. Originality/value: Repairing cracked MIG 29 jet engine inner flaps.

8

Laser repair hardfacing of titanium alloy turbine

Klimpel A., Janicki D., Lisiecki A., Rzeźnikiewicz A.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 49, nr 2

400--411

EN

Purpose: of this paper: work out repair technology of worn abutments of aircraft jet engine blades forged of titanium alloy WT3-1. Design/methodology/approach: The study were based on the analysis of laser HPDL powder surfacing of titanium alloy plates using wide range chemical composition consumables of titanium alloys and mixtures of pure titanium and spherical powder of WC indicated that very hard and highest quality deposits are provided by powder mixture of 40-50%Ti+60-50%WC. Findings: It was found that it is possible to achieve high quality deposits, free of any defects. HPDL technology can be used to repair worn turbine blade. Research limitations/implications: It was found that it is possible to repair the worn areas abutments of blades of zero compression stage of aircraft engine turbine by HPDL laser surfacing with using composite powder mixture of 50%Ti+50%WC as an additional material. Practical implications: The technology can be applied for repair worn abutments of aircraft jet engine blades. Originality/value: Repairing worn abutments of aircraft jet engine blades.

9

Hartowanie diodowym laserem dużej mocy

Pawłowicz W.

Obróbka Metalu

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2010

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nr 3

30--32

10

The comparision of tribological properties of the surface layer of the hot work tool steels obtained by laser alloying

Dobrzański L. A., Jonda E., Labisz K., Bonek M., Klimpel A.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 42, nr 1-2

142-147

EN

Purpose: The paper presents the investigation results of the influence of laser remelting or alloying on the abrasive wear resistance of the X40CrMoV5-1 and 32CrMoV12-28 hot work tool steels surface, using the high power diode laser (High Power Diode Laser). Design/methodology/approach: The main goal of this work was to compare the abrasion wear resistance of those two steels before and after laser treatment consisting on remelting or alloying with carbide powders. The reason of this work was also to determine the laser treatment parameters, particularly the laser power, to achieve surface layer with better properties for example hardness which is connected with abrasive wear resistance of surface layers. Findings: A modification of tool steels surface using a laser beam radiation, as well as coating them with special pastes containing particles such as vanadium 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. Surface layer obtained due to laser modification is characteristic of different properties than the native material. 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. Practical implications: The alloyed layers which were formed on the surface of the hot work steel have shown significant improvement. Good properties of the laser treatment make these layers suitable for various technical and industrial applications. Originality/value: Structural and tribological behaviour of surface layer achieved by alloying and remelting using high diode power laser and selected ceramic powders were compared.

11

Microstructure and properties of laser surface alloyed PM austenitic stainless steel

Brytan Z., Bonek M., Dobrzański L. A.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 40, nr 1

70-78

EN

Purpose: The purpose of this paper is to analyse the effect of laser surface alloying with chromium on the microstructural changes and properties of vacuum sintered austenitic stainless steel type AISI 316L (EN 1.4404). Design/methodology/approach: Surface modification of AISI 316L sintered austenitic stainless steel was carried out by laser surface alloying with chromium powder using high power diode laser (HPDL). The influence of laser alloying conditions, both laser beam power (between 0.7 and 2.0 kW) and powder feed rate (1.0-4.5 g/min) at constant scanning rate of 0.5m/min on the width of alloyed surface layer, penetration depth, microstructure evaluated by LOM, SEM x-ray analysis, surface roughness and microhardness were presented. Findings: The microstructures of Cr laser alloyed surface consist of different zones, starting from the superficial zone rich in alloying powder particles embedded in the surface; these particles protrude from the surface and thus considerably increase the surface roughness. Next is alloyed zone enriched in alloying element where ferrite and austenite coexists. The following transient zone is located between properly alloyed material and the base metal and can be considered as a very narrow HAZ zone. The optimal microstructure homogeneity of Cr alloyed austenitic stainless steel was obtained for powder feed rate of 2.0 and 4.5 g/min and laser beam power of 1.4 kW and 2 kW. Practical implications: Laser surface alloying can be an efficient method of surface layer modification of sintered stainless steel and by this way the surface chromium enrichment can produce microstructural changes affecting mechanical properties. Originality/value: Application of high power diode laser can guarantee uniform heating of treated surface, thus uniform thermal cycle across treated area and uniform penetration depth of chromium alloyed surface layer.

12

Structure and properties of surface layer of hot-work tool steels alloyed using high power diode laser

Dobrzański L. A., Jonda E., Labisz K.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

617-621

EN

Purpose: In this paper the results of remelting and alloying laser parameters on the structure and properties of the surface layer of the X40CrMoV5-1 and 32CrMoV12-28 hot work tool steels, using the high power diode laser (HPDL) are presented. Design/methodology/approach: The effect was determined of the main alloying parameters on hardness, abrasive wear resistance and roughness. The hot work tool steels conventionally heat treated were used as reference material and the tantalum carbide was used as an alloying material. The remelted layers which were formed in the surface of investigated hot work tool steels were metallographically examined and analyzed using a hardness testing machine. Findings: It was found out in examinations of the surface layer that it can be possible to obtain high quality top layer with higher hardness and abrasive wear resistance compared to material after conventional heat treatment. Research limitations/implications: The surface layer and its properties are elements which are critical for lifetime of tools and parts of machines and also for lifetime of whole technical equipment. If the working surface of a tool or its part is exposed to rough friction, an intensive mass and volume loss occurs. In this case it is reasonable to produce a surface layer which is extremely wear resistant to avoid the mass and volume loss. 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.

13

Effect of laser treatment on micro-structure and properties of cast magnesium alloys

Dobrzański L. A., Domagała-Dubiel J., Labisz K., Hajduczek E., Klimpel A.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 1

57-64

EN

Purpose: The goal of this paper is to present the structure and properties of the cast magnesium alloy after laser treatment. Design/methodology/approach: The laser treatment of magnesium alloys with TiC, WC powders was carried out using a high power diode laser (HDPL). The resulting microstructure in the modified surface layer was examined using optical microscopy, scanning electron microscopy and transmission electron microscope. Phase composition was determined by the X-ray diffraction method using the XPert device. The measurements of hardness and wear resistance of the modified surface layer were also studied. Findings: The region after laser treatment has a fine microstructure with hard carbide particles. Hardness of laser surface layer with both TiC and WC particles was 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 ěm. This investigation presents different laser power by one process speed rates. Practical implications: The results obtained in this investigation were promising towards 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 and titanium carbides.

14

Structure changes and mechanical properties of laser alloyed magnesium cast alloys

Dobrzański L., Domagała J., Malara S., Tański T., Kwaśny W.

Archives of Materials Science and Engineering

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2009

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Vol. 35, nr 2

77-82

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.

15

Laser surface treatment of the hot work tool steel alloyed with TaC and VC carbide powders

Dobrzański L. A., Jonda E., Klimpel A.

Archives of Materials Science and Engineering

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2009

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Vol. 37, nr 1

53-60

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.

16

Laser surface treatment of cast magnesium alloys

Dobrzański L., Domagała J., Tański T., Klimpel A., Janicki D.

Archives of Materials Science and Engineering

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2009

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Vol. 35, nr 2

101-106

EN

Purpose: The goal of this work was to investigate influence of laser treatment on structure and properties MCMgAl3Zn1, MCMgAl6Zn1, MCMgAl9Zn1 and MCMgAl12Zn1 cast magnesium alloys. Design/methodology/approach: Tests were made on the experimental MCMgAl3Zn1 MCMgAl6Zn1 MCMgAl9Zn1 and MCMgAl12Zn1 casting magnesium alloys. Laser treatment was made using the Rofin DL020 HPDL high power diode laser in the argon shield gas cover with the technique of the continuous powder supply to the remelted pool area. Findings: Investigations of the surface layers carried out confirm that laser treatment of the surface layer of the Mg-Al-Zn casting magnesium alloys is feasible using the HPDL high power diode laser ensuring better properties compared to alloys properties after the regular heat treatment after employing the relevant process parameters. Occurrences were found based on the metallographic examinations of the remelted zone (RZ) and the heat affected zone (HAZ) in alloyed surface layer of the investigated casting magnesium alloy. Research limitations/implications: This investigation presents different laser power and in this research was used two powders, namely tungsten-, and titanium carbide. Practical implications: Reinforcing the surface of cast magnesium alloys by adding TiC and WC particles is such a possible way to achieve the possibilities of the laser melt injection process, which is a potential technique to produce a Metal-Matrix Composite (MMC) layer in the top layer of a metal workpiece. Originality/value: The originality of this work is applying of High Power Diode Laser for alloying of magnesium alloy using hard particles like tungsten- and titanium carbide.

17

Structure and properties of the Mg alloys in as-cast state and after heat and laser treatment

Dobrzański L., Tański T., Domagała J., Król M., Malara S., Klimpel A.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 31, nr 2

123-147

EN

Purpose: The goal of this paper is to present the structure and properties of the magnesium cast alloys in as-cast state and after a heat treatment. Moreover in purpose of this paper is to extend a complex evaluation of magnesium alloys after laser surface treatment and the new methodology to determine the thermal characteristics of magnesium alloy using the novel Universal Metallurgical Simulator and Analyzer Platform (UMSA). Design/methodology/approach: Laser treatment of magnesium alloys alloyed with TiC, SiC, WC, VC, Al2O3 powders was carried out using a high power diode laser (HDPL). Experiments also were performed using the UMSA. Findings: The analysis of the thin foils after the ageing process has confirmed that the structure of the magnesium cast alloy consists of the Mg solid solution (matrix), of the secondary Mg17Al12 ß phase-evenly located in the structure. The structure creates agglomerates in the form of needle precipitations, partially coherent with the matrix, placed mostly at the grain boundaries. The alloyed region has a fine microstructure with hard carbide particles. The structure of the alloyed zone is dendritic. Microhardness of laser alloyed surface layer with ceramic powders was significantly improved compared to alloy without laser treatment. The research of the thermal analysis shows that UMSA Technology Platform is an efficient tool for collection and calculate of thermal parameters. Research limitations/implications: Totally there are some restriction for use of ceramic powders for alloying, some powders as oxides and nitrides are not favorable for alloying because of their dissolution during the alloying process. Further tests should be carried out in order to examine different cooling rates and parameters of solution treatment process and aging process. Investigations using the UMSA devices should concentrate on proper assessment of influence of different solidification rates on microstructure and mechanical properties.Originality/value: The originality of this work is applying of High Power Diode Laser for alloying of magnesium alloy using hard powders and also the Universal Metallurgical Simulator and Analyzer Platform.

18

Comparison of 32CrMoV12-28 steel alloyed with WC, VC and TaC powder using HPDL laser

Dobrzański L., Labisz K., Bonek M., Klimpel A.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 30, nr 2

187-192

EN

Purpose: This work presents the investigation results of laser remelting and alloying especially the laser parameters and its influence on the structure and properties of the surface of the 32CrMoV12-28 hot work steel, using the high power diode laser (HPDL). In this paper there are presented the investigation results of mechanical properties and microstructure with ceramic particle powders vanadium carbide VC, tungsten carbide WC and tantalum carbide TaC. The purpose of this work was also to determine the laser treatment conditions for surface layer treatment of the investigated steels. Design/methodology/approach: The purpose of this work was the determination of technological conditions for alloying and remelting of the surface layer particularly the laser power. There is studying the influence of treatment on the remelting depth of the surface layer to achieve high layer hardness for protection of the steel and also make the surface more resistant for work. Findings: As a result structure changes in form of fragmentation were determined. For alloying the tungsten carbide, tantalum carbide and vanadium carbide powders were used. Three phases of carbides: TaC, VC and WC, were observed. Research limitations/implications: The remelted layers which were formed on the surface of the investigated hot work steel were examined metallographically and analyzed using a hardness and micro hardness testing, X-ray diffraction, EDS microanalysis, electron scanning microscope. Practical implications: This work helps to use the new developed laser treatment technique for alloying and remelting of hot work tool steel tools for hot working conditions. Originality/value: The originality of this work is based on applying of High Power Diode Laser for improvement of steel mechanical properties as well the thermal fatigue and wear resistance.

19

Laser surface treatment of magnesium alloy with WC powder

Dobrzański L., Domagała J., Tański T., Klimpel A., Janicki D.

Archives of Materials Science and Engineering

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2008

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Vol. 30, nr 2

113-116

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 powders was carried out using a high power diode laser (HDPL). 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 morphology of the alloyed zone are dendrites. Microhardness of laser surface melted layer was significantly improved as compared to alloy without laser treatment. Research limitations/implications: This investigation presents different speed rates feed by one process laser power and in this research was used one powder with the particle size over 5µm. 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.

20

Characteristic of Mg-Al-Zn alloys after laser treatment

Dobrzański L. A., Domagała J., Tański T., Klimpel A., Janicki D.

Archives of Materials Science and Engineering

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2008

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Vol. 34, nr 2

69-74

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.