Ing. Lenka Klakurková, Ph.D.
E-mail:   klakurkova@fme.vutbr.cz  Dept.:   Institute of Materials Science and Engineering Dept. of Structural and Phase Analysis Position:   Research Worker Room:   A3/208

Supervised courses:

• Experimental Methods in Materials Engineering (WEM)
• Experimental Methods in Materials Engineering I (WEX)
• Practical Metallography (0PM)

Publications:

• ČELKO, L.; KLAKURKOVÁ, L.; ŠVEJCAR, J.:
  Diffusion in Al-Ni and Al-NiCr Interfaces at Moderate Temperatures,
  Defect and Diffusion Forum, Vol.297-301, (2010), No.2010, pp.771-777, ISSN 1012-0386, Trans Tech Publications
  journal article - other
• ČELKO, L.; KLAKURKOVÁ, L.; ŠVEJCAR, J.:
  Use of Powder Ligquid Method of Aluminide Diffusion Coatings Formation on Inconel 713 LC Nickel-Based Superalloy,
  Materials and Manufacturing Processes, Vol.24, (2009), No.10-11, pp.1155-1161, ISSN 1042-6914, Taylor and Francis
  journal article - other
• ČELKO, L.; KLAKURKOVÁ, L.:
  Effect of heat treatment on the Al+Si Diffusion coatings on Ni - based alloys,
  Chemické listy, Vol.102, (2008), No.S, pp.869-870, ISSN 0009-2770, Brno University of Technology, Faculty of Chemistry
  journal article - other
  akce: 4th Meeting on Chemistry & Life, Brno, 09.09.2008-11.09.2008
• KLAKURKOVÁ, L.; ČELKO, L.; DOLEŽAL, P.; MAN, O.; NĚMEC, K.:
  Elements interaction analyses during preparation of Al-Al3Ni eutectic composites,
  Chemické listy (S), Vol.102, (2008), No.S, pp.884-885, ISSN 1803-2389, Brno University of Technology, Faculty of Chemistry
  journal article - other
  akce: 4th Meeting on Chemistry & Life, Brno, 09.09.2008-11.09.2008
• KUBÁŇ, P.; PELCOVÁ, P.; KUBÁŇ, V.; KLAKURKOVÁ, L.; PURNENDU K., D.:
  Gravity-flow open tubular cation chromatography,
  Journal of Separation Science, Vol.2008, (2008), No.31, pp.2745-2753, ISSN 1615-9306, WILEY-VCH Verlag GmbH&Co. KGaA
  journal article - other

List of publications at Portal BUT

Abstracts of most important papers:

• ČELKO, L.; KLAKURKOVÁ, L.; ŠVEJCAR, J.:
  Diffusion in Al-Ni and Al-NiCr Interfaces at Moderate Temperatures,
  Defect and Diffusion Forum, Vol.297-301, (2010), No.2010, pp.771-777, ISSN 1012-0386, Trans Tech Publications
  journal article - other
  The diffusion couples for experimental study were prepared by HVOF spraying of nickel and nickel with 20wt.% of chromium powders onto the aluminium steet s surface. The interfaces with sharp gradient of chemical concentration of these elements were prepared. Annealing at the temperatures 600oC and 630oC, close to the Al+Al3Ni eutectic melting point (639,9oC), with different dwell times were realized. The reactants during the annealing diffuse and create layers of Al3Ni2 and Al3Ni intermediate phase compositions. Moreover, nickel without assistance of chromium diffuses preferably by using grain boundaries into aluminium substrate and produces the strengthening of the substrate by stable Al3Ni and metastable Al9Ni2 particles. The microstructures were obtained by scanning electron microscope. Layer theckness measurements were realized by means of image analyses. Chemical composition was estimated by energy dispersive microanalysis measurements. According to the results of these analyses performed the average chemical interdiffusion coefficients and Wagner s integral interdiffusion coefficients were calculated.
• ČELKO, L.; KLAKURKOVÁ, L.; ŠVEJCAR, J.:
  Use of Powder Ligquid Method of Aluminide Diffusion Coatings Formation on Inconel 713 LC Nickel-Based Superalloy,
  Materials and Manufacturing Processes, Vol.24, (2009), No.10-11, pp.1155-1161, ISSN 1042-6914, Taylor and Francis
  journal article - other
  Powder liquid method was used for aluminides diffusion coatings formation on the Inconel 713LC nickel-based superalloy. Two different powder mixtures (Al and Al+Si) in organic binder solution were prepared. Coating s depositoon onto the substrate surface was realized by spraying. Two-stage heat treatment under the argon-folw atmosphere was designed. First stage at 200oC was used to decompose organic binder. In the second stage at 1000oC the elements from the coating interact with the substrate. Protective intermetallic layer ane an interaction zone between the layer and substrate start to form. Elements interaction and phase transformations during annealing at 1000oC up to 600 min were studied. For this study the light micrtoscopy, scanning electron microscopy, energy dispersive microanalysis, x-ray diffraction phase analysis, microhardness measurement, and image analysis methods were used.
• ČELKO, L.; KLAKURKOVÁ, L.:
  Effect of heat treatment on the Al+Si Diffusion coatings on Ni - based alloys,
  Chemické listy, Vol.102, (2008), No.S, pp.869-870, ISSN 0009-2770, Brno University of Technology, Faculty of Chemistry
  journal article - other
  akce: 4th Meeting on Chemistry & Life, Brno, 09.09.2008-11.09.2008
  The nickel based alloys surface structure stability are recently ensured by use of many types of protective coatings. One of this types of coatings are diffusion ones. These coatings are based on saturation of Ni-based substrates with elements Al, Cr, Si or their combinations. This can lead to an improvement of the oxidation, corrosion and wear resistance of nickel based alloys surfaces. This papers deals with preparation of Al+Si diffusion coatings on the nickel based substrates from slurries annealed at 1000oC. The phase transformations and element interactions were studied. As a substrate, Ni of commercial purity, Ni20Cr and Inconel 713LC alloys were used. During annealing, the elements from coating intgeract with the substrate while forming intermetallic protective layer and an interaction zone between the protective layer and substrate. For this study the light microscopy, scanning electron microscopy, energy dispersive microanalyses, microhardness measurements and image analysis methods were used.
• KLAKURKOVÁ, L.; ČELKO, L.; DOLEŽAL, P.; MAN, O.; NĚMEC, K.:
  Elements interaction analyses during preparation of Al-Al3Ni eutectic composites,
  Chemické listy (S), Vol.102, (2008), No.S, pp.884-885, ISSN 1803-2389, Brno University of Technology, Faculty of Chemistry
  journal article - other
  akce: 4th Meeting on Chemistry & Life, Brno, 09.09.2008-11.09.2008
  Understanding of equilibrium and non-equilibrium thermodynamic phase transformations is one of the basic condition for design of intermetallic particle strenghted composites. The Al-Ni binary systems is already used for high teamperature applications (Nickel based superalloys and high temperature protective coatings) where the Ni3Al and NiAl intermetalics widely appear. But this system contains another intermetallic compounds Al3Ni, Al3Ni2, Al3Ni5 which are neglected in high temperature studies. These intermetallic compounds can be employed as sternghtening phases in Al-based composites. The advantages of these materials are low density and relatively good chemical resistance. They can reach attractive properties in combination with less known Al-Ni intermatallic phases strenghtening. This paper is focused on the developement of Al-based composites prepared by HVOF nickel powder deposition on Al substrate. Use of this method alone is menting point of pure Al. The temperatures for difusion and formation of this intermetallics phases are in the range from 600 to the 630oC. For this study the light microscopy, scanning electron microscopy, energy dispersive microanalyses and image analyses were used.
• KUBÁŇ, P.; PELCOVÁ, P.; KUBÁŇ, V.; KLAKURKOVÁ, L.; PURNENDU K., D.:
  Gravity-flow open tubular cation chromatography,
  Journal of Separation Science, Vol.2008, (2008), No.31, pp.2745-2753, ISSN 1615-9306, WILEY-VCH Verlag GmbH&Co. KGaA
  journal article - other
  We describe ion chromatography (IC) on open tubular cation exchange columns with a controllable capacity multilayered stationary phase architecture. The columns of relatively large bore (75 lm id) are fabricated by coating fused-silica capillaries with multiple layers of poly(butadiene-maleic acid) (PBMA) copolymer and crosslinking the deposited layers by thermally initiated radical polymerisation. Column capacity increases in a predictable manner with increase in the number of successively coated layers. Gravity flow with a modest head (a2 m) can provide the desired separations within a reasonable period. We provide a minimalist configuration where no suppression is used, the sample is injected hydrodynamically as in CE, and detection is accomplished by an inexpensive homebuilt contactless conductivity detector or a capacitance to voltage digital converter. A 1 m long 75 lm bore column coated with two layers of PBMA allows gravity-flow open tubular IC to separate four alkali cations in a10 min with a 1 mM tartaric acid (TA) eluent. Simultaneous separation of alkali and alkaline earth metal cations can be accomplished in less than 25 min using 1.75 mM pyridinedicarboxylic acid as an eluent. Contactless conductometric detection (C4D) allows LODs down to 150 nmol/L, corresponding to 30 fmol injections. Analysis of real water samples is demonstrated.