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1

Effect of Laser Feeding on Heat Treated Aluminium Alloy Surface Properties

100%

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.

2

Improvement of the hot work tool steel surface layers properties using a high power diode laser

72%

Dobrzański L. A. , Piec M. , Klimpel A.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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tom Vol. 21, nr 1

13-22

EN

Purpose: The purpose of this research paper is focused on the X38CrMoV5-3 hot work tool steel surface layers properties using HPDL laser. Design/methodology/approach: The aim of this research paper is to present deposition technologies, investigation of structure and properties of the X38CrMoV5-3 hot work tool steel alloying with ceramic particles using high power diode laser HPDL. Selection of laser operating conditions is discussed, as well as beam face quality after remelting, hardness, micro hardness test, wear resistant, EDX, TEM and X-ray microanalysis results. Findings: The structure of the solidified material after the laser remelting is characterized by the diversified morphology connected with the multiple changes of the crystal growth direction from little dendrites to tiny equiaxed grains in the near-surface zone. The main axes of the dendrites are directed according to the heat abstraction directions on the border of the solid and liquid phases with the carbides' clusters arranged according to the whirls caused by a convectional movement in the pool of the metallic liquid as well as partly unremelted conglomerates NbC, TaC, VC, WC and TiC as a melting material in the middle area of the remelted zone. Research limitations/implications: Laser technique features the especially promising tool for solving the contemporary surface engineering problems thanks to the physical properties of the laser, making it possible to focus precisely the delivered energy in the form of heat in the surface layer. Practical implications: Practical implications are: regeneration and manufacturing of various tools from the X38CrMoV5-3 hot-work tool steel. Originality/value: The laser treatment as a part of the new generation techniques applied in metal surface technology.

3

Thermal analysis of nozzle for powder feeding in High Power Diode Laser (HPDL) powder surfacing

72%

Klimpel A. , Janicki D. , Lisiecki A.

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tom Vol. 20, nr 1-2

463-466

EN

Purpose: Purpose of these researches was to determine the influence of High Power Diode Laser (HPDL) powder surfacing parameters, material type and shape of the nozzle for powder feeding on the temperature field of the nozzle. Design/methodology/approach: Different materials for manufacturing of the nozzle for powder feeding during HPDL powder surfacing and different shapes of the nozzle were tested to establish the optimum shape and select the material that ensure lowest heating of the nozzle. Reflection coefficient of the infared laser radiation of 808 nm for the tested materials were determined as a function of a temperature. Temperature of the nozzle tip was measured and determined as a function of surfacing parameters. Life time of the different nozzles was determined. Findings: It was shown that the nozzle made of copper body and thin-walled tube made of austenitic stainless steel ensures much higher life time of the nozzle and also higher process efficiency compared with nozzle made of copper. Research limitations/implications: It was found that decreasing the distance from the nozzle tip of thin-walled tube made of austenitic stainless steel to the weld pool surface resulted in increasing of the process efficiency but too short distance is the reason of extensive heating of the nozzle. Originality/value: The optimized shape of the powder feeding nozzle made of thin-walled tube made of austenitic stainless steel guarantee unlimited lifetime of the nozzle and high surfacing efficiency over 95%.

4

Study of laser welding of copper sheets

72%

Klimpel A. , Rzeźnikiewicz A. , Janik Ł.

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tom Vol. 20, nr 1-2

467-470

EN

Purpose: Purpose of this research is to study laser autogeneous welding process of short seam beads and fillet welds of lap joints of oxygen-free copper sheets 1.0 [mm] thick. On the bases of results of quality assessment it was proved that high power diode laser (HPDL) welded lap joints of copper sheet provide mechanical properties on the level of parent material. Design/methodology/approach: Short seam beads and fillet welds of lap joints of oxygen-free copper sheets 1,0 [mm] thick were tested, to establish the optimum parameters of high power diode laser autogeneous welding process. Findings: It was shown that there is very narrow range of optimum HPDL autogeneous welding parameters of short seam beads and fillet welds of lap joints of oxygen-free copper sheets 1,0 [mm] parameters. It was proved that high power diode laser (HPDL) autogeneous welded lap joints provide mechanical properties on the level of parent material. Practical implications: It is possible to produce high quality short seam bead and fillet weld lap joints of oxygen-free copper sheets 1.0 [mm] thick. It was proved that high power diode laser (HPDL) autogeneous welded lap joints provide mechanical properties on the level of parent material. Originality/value: The optimum HPDL autogeneous welding parameters of short seam beads and fillet welds of lap joints of oxygen-free copper sheets 1.0 [mm] parameters makes possible to produce high quality laser autogeneous welded lap joints of copper sheets 1.0 [mm] thick.

5

Computer aided structure prediction of OH18N9 and S235JR steels laser welded joints

58%

Klimpel A. , Kik T. , Górka J.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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tom Vol. 21, nr 1

83-86

EN

Purpose: of these researches was to investigate possibilities of joining materials with different chemical composition and properties. CAW software to prediction of joints structure was used. Design/methodology/approach: the quality of single- and double sided joints was assessed by metallographic examinations, hardness tests, tensile and bending tests. Findings: a computer aided structure prediction was tested by metallographic examinations and hardness tests. Because of possibility of use these type of joints in medical equipment production tensile and bending tests and also corrosion resistance tests were performed. Research limitations/implications: for complete information about tested different chemical composition and properties materials joints it is needed to check others materials in place of S235JR carbon steel. Practical implications: result of this paper is an information that is possible to join materials with different chemical composition and properties materials with different chemical composition and properties. It also possible to precise predict structure of weld using computer software. Originality/value: the researches were provided for welding materials used in medical equipment producing. Welded joints were tested for a corrosion resistance in typical disinfectants used in medical conditions. At the beginning computer prediction was used.