Wyniki wyszukiwania - Biblioteka Nauki

1

TEM microstructure investigations of aluminium alloys used for laser alloying

100%

Labisz K. , Kurpiński M. , Tański T.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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tom Vol. 55, nr 2

734--741

EN

Purpose: In this paper there are presented results of Transmission Electron Microscope investigation concerning the structure of the AlSi7Cu4 cast aluminium alloy using for alloying and remelting with the high power diode laser (HPDL). There are also presented the results of the thermo-derivative analysis performed using the UMSA (Universal Metallurgical Simulator and Analyser) device, allowing to determine the specific points of the solidifying alloy, what is helpful for phase determination occurred in this alloy. In this work especially the changes of the precipitation type, size and shape were determined. Design/methodology/approach: The investigations were performed using electron microscopy for the microstructure and phases determination. By mind of the transmission electron microscopy, especially selected area diffraction method appliance it was possible to determine the phases occurred in the alloy in the as cast state. The morphology and size of the Mg2Si was also possible to determine as well the lattice parameters for this phase. Findings: The reason of this work was also to present the laser treatment technology, which will be used for further alloying and remelting with ceramic powders - especially carbides and oxides. Particularly the overview will be directed on the laser power to achieve good layer hardness for protection of this hot work tool steel from losing their work stability and to make the tool surface more resistant to action in external conditions. The structure of the surface laser tray changes in a way, that there are very high roughness of the surface zone and the flatness or geometry changes in an important manner, crucial for further investigation. Research limitations/implications: The aluminium samples were examined metallographically using transmission electron microscope with different image techniques. Practical implications: Developing of new technology with appliance of Al alloys, High Power Diode Laser and diverse ceramic powders will be possible to obtain, based in findings from this research project. Some other investigation should be performed in the future, but the knowledge found in this research concerning the proper process parameters for each type of alloy shows an interesting investigation direction. Originality/value: The combination of metallographic investigation for cast aluminium alloys - including electron microscope investigation - and HPDL treatment parameters makes the investigation very attractive for automobile, aviation industry, and others where aluminium alloys plays an important role.

2

Effect of laser surface treatment on the quality of microstructure in recycled Al-Zn-Si cast alloy

88%

Tillova E. , Durinikova E. , Chalupova M. , Radek N.

Production Engineering Archives

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2014

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tom Vol. 2, No. 1

26--32

EN

Recycled Al-Zn-Si casting alloys can often be used in new cast products for mechanical engineering, in hydraulic castings, textile machinery parts, cable car components or big parts without heat treatment. Improved mechanical properties and favourable of recycled microstructure of Al-alloys can often significantly increase the lifetime of casting and reduce costs for fuel and reduction of environmental loading. The paper is focused on using one of possible technologies that provide increased mechanical properties of recycled aluminium cast alloys for automotive industry, and that is laser surface hardening. For study was used recycled AlZn10Si8Mg cast alloy. The effect of laser beam Nd: YAG lasers BLS 720 was evaluated with the laser power 50 W and 80 W on the surface of samples. The final microstructure of aluminium alloys depend on the laser process parameters. The changes of microstructure as a grain refinement of the microstructure after laser surface hardening was observed by using classical techniques of etching and deep etching with concentrated HCl. Microstructure was evaluated on an optical microscope Neophot 32 and SEM.

3

Effect of Laser Feeding on Heat Treated Aluminium Alloy Surface Properties

88%

Labisz K. , Tański T. , Janicki D. , Borek W. , Lukaszkowicz K. , Dobrzański L. A.

Archives of Metallurgy and Materials

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2016

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tom Vol. 61, iss. 2A

741--746

EN

In this paper are presented the investigation results concerning microstructure as well as mechanical properties of the surface layer of cast aluminium-silicon-copper alloy after heat treatment alloyed and/ or remelted with SiC ceramic powder using High Power Diode Laser (HPDL). For investigation of the achieved structure following methods were used: light and scanning electron microscopy with EDS microanalysis as well as mechanical properties using Rockwell hardness tester were measured. By mind of scanning electron microscopy, using secondary electron detection was it possible to determine the distribution of ceramic SiC powder phase occurred in the alloy after laser treatment. After the laser surface treatment carried out on the previously heat treated aluminium alloys, in the structure are observed changes concerning the distribution and morphology of the alloy phases as well as the added ceramic powder, these features influence the hardness of the obtained layers. In the structure, there were discovered three zones: the remelting zone (RZ) the heat influence zone (HAZ) and transition zone, with different structure and properties. In this paper also the laser treatment conditions: the laser power and ceramic powder feed rate were investigated. The surface laser structure changes in a manner, that there zones are revealed in the form of. This carried out investigations make it possible to develop, interesting technology, which could be very attractive for different branches of industry.

4

HPDL laser alloying of Al-Si-Cu alloy with Al2O3 powder

63%

Labisz K. , Tański T. , Dobrzański L. A. , Janicki D. , Korcina K.

Archives of Materials Science and Engineering

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2013

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tom Vol. 63, nr 1

36--45

EN

Purpose: This article presents results of investigation of laser alloyed cast aluminium alloys after standard heat treatment. In general into the aluminium matrix there are fed different types of ceramic particles including aluminium oxide. The purpose of this work was also to determine the laser treatment conditions for surface hardening of the investigation alloys, like laser power, as well the laser scan rate. Design/methodology/approach: The investigations were performed using light and electron microscopy (SEM) for structure determination, using EDS microanalysis it was also possible to determine the chemical composition changes. The morphology and size of the ceramic powder particles was also possible to determine. Findings: Concerning the laser treatment conditions for surface hardening the scan rate as well as the laser power influence was studied. The structure of the surface laser tray changes in a way, that there are very high roughness of the surface zone and the flatness or geometry changes. Research limitations/implications: The aluminium samples were examined metallographically using optical microscope with different image techniques as well as scanning electron microscope. Practical implications: Developing of new technology with appliance of Al alloys, High Power Diode Laser and diverse ceramic powders can be possible to obtain, based in findings from this research project. Some other investigation should be performed in the future, but the knowledge found in this research concerning the proper process parameters for each type of alloy shows an interesting investigation direction. Originality/value: The combination of metallographic investigation, including electron microscope investigation and High Power Diode Laser (HPDL) treatment parameters makes the investigation very attractive especially for automobile industry, and transportation where parts manufactured of aluminium alloys are a very important because of its surface properties.

5

Unique properties, development perspectives and expected applications of laser treated casting magnesium alloys

63%

Dobrzańska-Danikiewicz A. D. , Tański T. , Domagała-Dubiel J.

Archives of Civil and Mechanical Engineering

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2012

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tom Vol. 12, no. 3

318--326

EN

The purpose of the article is to present the unique properties of casting magnesium alloys subjected to surface treatment with the high power diode laser, to indicate the development outlooks of the technology and to present its application opportunities in the automotive industry. The laser alloying and cladding of hard titanium and tungsten carbides particles into the substrate surface improves the mechanical and functional properties of the investigated materials to a satisfactory extent. In view of the demand from the automotive sector for components and parts made of lightweight alloys, the development prospects of their effective manufacturing technology meeting the expected product properties, including surface laser treatment, were evaluated to be very high.

6

Applications of lasers in metallization of thermoplastic and thermosetting polymers

63%

Rytlewski P. , Żenkiewicz M.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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tom Vol. 57, nr 2

59--67

EN

Purpose: This work focuses on the studies of chemical and physical changes induced by ArF-laser irradiation leading to formation of surfaces catalytically highly active and fully prepared for the direct electroless metallization for the case of thermoplastic and thermosetting polymer composites. The only pretreatment method for surface to be activated was laser irradiation. There are compared two polymer composites: thermoplastic and thermosetting with the same qualitative and quantitative contents of the selected copper compounds. Additionally, there is presented wide context of laser applications in electroless metallization of polymeric materials. Design/methodology/approach: The composites contained the same amount of copper(II) oxide (CuO) and copper(II) acetoacetate Cu(acac)2, while varied with the type of polymer matrix. There were chosen polyamide 6 as thermoplastic and polyurethane resin as thermosetting polymer matrixes. The composites were irradiated with various numbers of ArF excimer laser pulses (λ = 193 nm) at constant fluence of 100 mJ/cm2. The metallization procedure of the laser-irradiated samples was performed by use of a commercial metallization bath and formaldehyde as a reducing agent. The samples were examined using FTIR, contact angle measurement and SEM techniques. Findings: It was found that laser irradiation induce catalytic properties in the studied composites. However, better catalytic properties were achieved for the thermoplastic than thermosetting polymer composites. Research limitations/implications: In order to better understand the differences in laser interactions between thermoplastic and thermosetting composites more examples of various polymer matrixes should be investigated. Practical implications: Suitable condition for laser irradiation of the composites associated with the best catalytic properties were proposes. Better catalytic properties were achieved for thermoplastic than thermosetting composite. Originality/value: Comparison of new thermoplastic and thermosetting polymer composites intended for laser direct electroless metallization is firstly reported in this article.

7

Fractographic and structural peculiarities of laser weld-on layers with a maraging alloy

63%

Shtarbakov V. , Stavrev D.

Archives of Materials Science and Engineering

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2015

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tom Vol. 75, nr 1

12--17

EN

Purpose: Purpose of the present paper is to investigate the fractographical peculiarities of the layers welded-on the surface of 30CrMoV12-28 (DIN) tool steel by laser with additional material of marraging alloy. Design/methodology/approach: The operation was accomplished on an AL 200 automatic weld-on machine with an Nd:YAG pulse resonator providing a beam of 1064 nm wavelength. The mean power output of the pulse was 200 W and the maximum peak power output was 10 kW. The operating frequency was 20 Hz. The diameter of the laser beam focused on the sample surface was 0.6 mm. The weld-on maraging alloy featured contents of 0.02C - 0.2Si - 0.2Mn - 2Cr - 19.3Ni - 0.4V - 4.7Mo - 14.5Co - 0.25Al, wt%. Studied were the fractures obtained at three - point bending of the layer upon weld-on followed by two - hour age hardening at temperatures of 550 and 600°C. Findings: The nature of deformation along the weld-on layer under tensile impact strains was studied, the destruction being trans-crystalline determined by the prevailing plastic deformation.The destruction after age hardening at temperatures of 550 and 600°C was of the mixed and trans-crystalline type. The results of the processes of dispersion hardening and those of the beginning of coherent phase formation were connected with the main matrix of the inter-metallic compounds based on NiAl and NiMo. The condition of the structure was characterized by the so called “pit” curved surface of the destruction. The analysis of the fractures along with the EDS analysis showed that the inter-metallic phases formed in the process of secondary hardening of the material in the weld-on layer were of the NiAl, NiMo and Ni3Mo type. Research limitations/implications: For more correct determination of phase contents in depth of hardened layers have to be used XRD techniques. Practical implications: Taking into account the high value of the materials used for producing press-forming dies it is of vital importance to find possibilities for considerable increase of the lifecycle of casting moulds. Laser surface welding-on by using of maraging alloy as additional material is cost effective technology for repairing of press-forming dies.

8

Precipitation evolution and surface modification of magnesium alloys

51%

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

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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tom Vol. 61, nr 2

87--149

EN

Purpose: The purpose of this publication is to present the results of own long-term research summarising the experience concerning as casting magnesium alloys, and in especially a thermal analysis describing the process of alloys crystallisation, standard heat treatment according to the occurring phase transitions and precipitation processes, surface treatment with the CVD and PVD methods, laser surface treatment of surface layers, as well as using the methods of Computer Materials Science. Design/methodology/approach: The research concerned in the first place an analysis of Mg-Al-Zn alloys crystallisation kinetics. Optimisation investigations for heat treatment conditions taking into consideration different cooling mediums were performed in order to identify fully the structure of the investigated magnesium casting alloys. Investigations were carried out of the structure and properties of coatings produced with the CVD and PVD methods on the investigated Mg-Al-Zn alloys. The last stage of investigating the presented Mg-Al-Zn alloys applied to laser surface treatment enabling to produce a quasi-composite structure of MMCs characterised by the gradient of phase composition as well as functional properties by feeding hard ceramic particles, in particular carbides and oxides, into the surface of the materials produced. Findings: Valuable and original results were achieved based on the broad scope of the research performed both, in cognitive and applicational terms, concentrated mainly on the analysis and influence of chemical composition and technological heat and surface treatment processes on the structure and properties of the investigated alloys. Practical implications: The properties of the core and surface layer of the part produced can be customised most advantageously by selecting the part’s material and its structure and properties formation processes appropriately along with the surface layer type and technology ensuring the required functional properties. Originality/value: The knowledge gathered for years concerning light metal alloys, and in particular Mg-Al-Zn alloys, of an undoubtedly valuable cognitive character, is dedicated not only to students but also postgraduates and researches to improve the conditions of education.

9

Foresight methods application for evaluating laser treatment of hot-work steels

51%

Dobrzańska-Danikiewicz A. D. , Jonda E. , Labisz K.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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tom Vol. 43, nr 2

750--773

EN

Purpose: The purpose of this article is to evaluate the strategic growth perspectives of laser treatment of X40CrMoV5-1 and 32CrMoV12-28 hot-work alloy tool steels using NbC, TaC, TiC, VC and WC carbide powders. The criterion assumed for dividing the technologies into groups was the powder type; thus, five groups were selected to realised researches. Design/methodology/approach: As a part of the foresight-materials science researches, a dendrological matrix of technology value, a meteorological matrix of environment influence, and a matrix of strategies for technologies were elaborated, the strategic development tracks were determined, and materials science experiments were conducted using a scanning electron microscope, an optical microscope, a transmission electron microscope, a microhardness tester, a scratch tester, an X-ray diffractometer, an electron microprobe X-ray analyzer and a device for testing of heat fatigue and abrasive resistance. Also, technology roadmaps were prepared. Findings: The researches conducted demonstrated huge potential and attractiveness of the analyzed technologies, compared to others, and the promising properties improvement of the tested surface layers, as a result of laser surface treatment. Research limitations/implications: Researches concerning laser treatment of hot-work alloy tool steels constitute a part of a larger research project aimed at identifying, researching, and characterizing the priority innovative technologies in the field of materials surface engineering. Practical implications: The presented results of experimental materials science researches prove the significant positive impact of laser treatment on the structure and the properties of hot-work alloy tool steels, which justifies including them in the set of priority innovative technologies recommended for use in small and medium enterprises and in other business entities. Originality/value: The value of this article lies in the fact that it determines the value of laser treatment of hot-work alloy tool steels compared to other technologies and identifies the recommended strategic development tracks and technology roadmaps for them, taking into account the impact of such treatment on hardness, abrasion resistance, and coarseness of the tested surface layers.

10

Koncepcja i rezultaty laserowej obróbki powierzchniowej stopów aluminium o temperaturze kriogenicznej.

51%

Serbiński W.

Inżynieria Materiałowa

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2000

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tom R. XXI, nr 6

434-437

PL

W pracy przedstawiono koncepcję procesu i efekt oddziaływania wiązki lasera na powierzchnię stopów aluminium o temperaturze kriogenicznej. Uzyskano wyraźną zmianę mikrostruktury stopów AlSi10Cu2Mg1Ni1 i AlSi13Mg1CuNi w obszarze oddziaływania wiązki lasera oraz gwałtownego chłodzenia. W rezultacie ukształtowano warstwę wierzchnią stopów aluminium o twardości kilkakrotnie wyższej od ich twardości konwencjonalnej. Stwierdzono, iż głębokość przetopionej warstwy przy ciągłej 1,2 kW mocy lasera CO2 i stałej średnicy wiązki maleje wraz ze wzrostem prędkości przesuwu obrabianego elementu względem nieruchomego laserowego źródła ciepła.

EN

The method and equipment for laser treatment of the aluminium alloys at the cryogenic temperature have been proposed. The influence of laser beam on the surface layer of the aluminium alloys at cryogenic temperature is observed. Significant changes in microstructures of AlSi10Cu2Mg1Ni1 and AlSi13Mg1CuNi alloys in the laser treated zone were obtained. The surface layers of the hardness 211+280 HV0,05, several times higher than after conventional heat treatment of the aluminium alloys, were created. It was found, that the depth of the remelted layer for the laser CO2 with a power of 1,2 kW and the stable laser beam diameter decreased together with increase of the motion velocity of the treated element relative to the immovable laser beam.

11

Report on the main areas of the materials science and surface engineering own research

44%

Dobrzański L. A.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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tom Vol. 49, nr 2

514--549

EN

Purpose: The purpose of the paper is to present the representative examples for the own scientific research in the area of the forming of the structure and properties of engineering materials including biomaterials, their properties testing and microstructure characterisation and modelling, simulation and prediction of the properties and structure of these materials after selected materials processing technologies. Design/methodology/approach: The main areas of the scientific interests reported in this paper on the basis of the own original research include forming of structure and properties of engineering materials including biomaterials using advanced synthesis and materials processing technologies and nanotechnologies, engineering materials including biomaterials properties testing and microstructure characterisation using very advanced contemporary research methodologies including electron microscopy, modelling, simulation and prediction of properties and structure of engineering materials including biomaterials using advanced methods of computational materials science including artificial intelligence methods. Findings: A general character of the paper concerning many aspects of material science research enabled a detailed description of research methodology and details concerning research results. Detailed information is included in many detailed cited works. Practical implications: Presented research results can be used in practice. Originality/value: The paper presents numerous research results which Has been made during last years generalising the achievements of the research team directed by the author.