Browsing Acta Polytechnica CTU Proceedings. 2020, vol. 27 by Issue Date

Now showing items 1-20 of 31

    • RELATION BETWEEN HARDNESS OF (Ti, Al)N BASED MULTILAYERED COATINGS AND PERIODS OF THEIR STACKING 

      Author: Zaoui, Mehdi; Bourceret, Alexandre; Gaillard, Yves; Giljean, Sylvain; Rousselot, Christophe; Pac, Marie-José; Richard, Fabrice
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      This study aims to model, by using a finite element method, the relationship between the hardness and the period Λ of metal/nitride multilayer coatings (Ti0.54Al0.46/Ti0.54Al0.46N)n in order to understand the increase of ...

    • MICRO-SCALE STUDY OF RESIDUAL STRESSES IN CR2O3 COATINGS SPRAYED BY APS 

      Author: Decroos, Franck; Langlade, Cécile; Bourillot, Eric; Darut, Geoffrey; Francois, Manuel
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Whichever the application field, every material forming process generates residual stresses on the surface. While they are likely to enhance the aimed properties of the final mechanical part, these stresses may also ...

    • EVALUATION OF INTERNAL COHESION OF MULTIPHASE PLASMA-SPRAYED COATINGS BY CAVITATION TEST: FEASIBILITY STUDY 

      Author: Mušálek, Radek; Nardozza, Emanuele; Tesař, Tomáš; Medřický, Jan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Mechanical characterization of plasma-sprayed coatings at microscopic level represents a major challenge due to the presence of numerous inherent microstructural features such as cracks, pores, or splat boundaries, which ...

    • DYNAMIC IMPACT WEAR AND IMPACT RESISTANCE OF W-B-C COATINGS 

      Author: Daniel, Josef; Grossman, Jan; Buršíková, Vilma; Zábranský, Lukáš; Souček, Pavel; Mirzaei, Saeed; Vašina, Petr
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Coated components used in industry are often exposed to repetitive dynamic impact load. The dynamic impact test is a suitable method for the study of thin protective coatings under such conditions. Aim of this paper is to ...

    • COMPARISON OF Mo COATING DEPOSITED BY TWAS AND APS SinplexPro THERMAL SPRAY TECHNIQUES 

      Author: Houdková, Šárka; Antoš, Jakub; Šulcová, Petra; Lencová, Kateřina; Hajšman, Jan; Burdová, Karolína; Duliškovic, Josef
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      The wear resistant Mo coatings were deposited using SmartArc Electric Arc Wire Spray System and advanced SinplexPro high throughput atmospheric plasma spray gun. The coatings were analyzed in terms of microstructure, ...

    • HARDNESS OF NITRIDED LAYERS TREATED BY PLASMA NITRIDING 

      Author: Joska, Zdeněk; Pokorný, Zdeněk; Kadlec, Jaromír; Studený, Zbyněk; Svoboda, Emil
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Stainless steels, particularly the austenitic stainless grades are widely used in many industries due to good corrosion resistance, but very poor mechanical properties as surface hardness and wear resistance limit its ...

    • LASER-INDUCED SURFACE ACOUSTIC WAVES FOR THIN FILM CHARACTERIZATION 

      Author: Kudělka, Radim; Václavek, Lukáš; Tomáštík, Jan; Malecová, Sabina; Čtvrtlík, Radim
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Knowledge of mechanical properties of thin films is essential for most of their applications. However, their determination can be problematic for very thin films. LAW (Laser-induced acoustic waves) is a combined acousto-optic ...

    • HARDNESS OF HYBRID PVD-PECVD W-C:H COATINGS VS. SUBSTRATE TYPE 

      Author: Lofaj, František; Kabátová, Margita
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      The effects of substrate on the measurement of hardness (and indentation modulus) - penetration depth profiles were investigated on hybrid PVD-PECVD W-C:H coatings made with the additions of C2H2 or CH4 using High Power ...

    • ON THE DESIGN OF COATING SYSTEM USING NANOMECHANICAL EXPERIMENTS 

      Author: Mercier, David; Fredriksson, Claes
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      The aim of this paper is to identify performance indices for the design of coating systems, using results from nanomechanical tests. The use of nanoindentation, nanoscratch and pin-on-disk experiments applied to coatings ...

    • MICROSTRUCTURE AND MICROHARDNESS EVALUATION FOR NiCrAlY MATERIALS MANUFACTURED BY SPARK PLASMA SINTERING AND PLASMA SPRAYING 

      Author: Hulka, Iosif; Mušálek, Radek; Lukáč, František; Klečka, Jakub; Chrástka, Tomáš
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      NiCrAlY deposited by different thermal spraying methods is commonly used as the bond coat material in thermal barrier coatings (TBCs). In the present study, two experimental coatings were deposited by hybrid water stabilized ...

    • LOCAL MECHANICAL PROPERTIES OF ATMOSPHERIC SPRAYED MOLYBDENUM COATINGS DEPOSITED WITH CASCADED PLASMA TORCH 

      Author: Antoš, Jakub; Šulcová, Petra; Lencová, Kateřina; Houdková, Šárka; Duliškovic, Josef; Hajšman, Jan; Burdová, Karolína; Račický, Antonín
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Increasing interest for industrial use of thermally sprayed coatings leads to development in most thermal spraying technologies, including atmospheric plasma spraying (APS). The latest cascaded torch SinplexPro from Oerlikon ...

    • FRACTURE BEHAVIOR OF FeAlSi INTERMETALLICS 

      Author: Čech, Jaroslav; Haušild, Petr; Karlík, Miroslav; Nová, Kateřina; Průša, Filip; Novák, Pavel; Kopeček, Jaromír
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      The study is devoted to the intermetallic alloy FeAl20Si20 (wt.%) with the potential applications in high temperature aggressive environments. The samples of the same chemical composition were prepared by spark plasma ...

    • COMPRESSION OF ECAPED TITANIUM MICRO-PILLARS FOR TWO PRINCIPAL ORIENTATIONS 

      Author: Vokoun, David; Maňák, Jan; Tesař, Karel; Habr, Stanislav
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      The thermomechanical processing by equal-channel angular pressing (ECAP) is used for certain metals and alloys in order to make their structure fine and to increase material strength. In the previous study done at our ...

    • ROLE OF FLUID ON THE CONTACT DEFORMATION RESPONSE OF BIOLOGICAL TISSUE 

      Author: Swain, Michael V.
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      This paper will focus on the role of fluids on the indentation deformation response of tooth and eye tissues. All natural biological materials contain fluid and function in a fluidic environment, which plays a critical ...

    • MATHEMATICAL MODELING OF EXPERIMENT ON BERKOVICH NANOINDENTATION OF ZRN COATING ON STEEL SUBSTRATE 

      Author: Sadyrin, Evgeniy; Vasiliev, Andrey; Volkov, Sergei
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      In the present paper the experiment on Berkovich nanoindentation of ZrN coating on steel substrate is modelled using the proposed effective mathematical model. The model is intended for describing the experiments on ...

    • MECHANICAL PROPERTIES OF FORGED TUNGSTEN HEAVY ALLOYS 

      Author: Kovářík, Ondřej; Čech, Jaroslav; Čapek, Jiří; Hajíček, Michal; Klečka, Jakub; Siegl, Jan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Tungsten heavy alloys are composite materials containing spherical tungsten particles embedded in binder matrix. Their excellent mechanical properties can be further improved by rotary forging. This paper aims to gain ...

    • NANOINDENTATION OF HYDROGEN ENRICHED Zr-1Nb ZIRCONIUM ALLOY NUCLEAR FUEL CLADDINGS 

      Author: Libera, Ondřej; Halodová, Patricie; Gávelová, Petra; Krejčí, Jakub
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Zirconium alloys are being commonly used as a material of choice for nuclear fuel claddings in water cooled nuclear reactors for decades due to their good corrosion resistance and low neutron absorption. However, the ...

    • INDENTATION SIZE EFFECT IN HIGH PRESSURE TORSION PROCESSED HIGH ENTROPY ALLOY 

      Author: Haušild, Petr; Čížek, Jakub; Čech, Jaroslav; Zýka, Jiří; Kim, Hyoung Seop
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      High entropy alloy HfNbTaTiZr in as cast conditions and after high pressure torsion straining was characterized by nanoindentation. The length-scale dependent material response (indentation size effect) was characterized ...

    • HOT HARDNESS MEASUREMENTS ON MATERIALS UP TO 600 °C DURING THE FIRST HOUR OF USING 

      Author: Passilly, Bruno; Molenda, Lara
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      In the aeronautical field, materials are used in severe environmental conditions (temperature, atmosphere, exposure time ...), particularly for engine applications. In order to characterize the use of these materials in ...

    • COMPARISON OF TWO TECHNIQUES FOR EVALUATING SPHERICAL INDENTATION DATA 

      Author: Materna, Aleš; Haušild, Petr; Ondráček, Jan
      (České vysoké učení technické v PrazeCzech Technical University in Prague, 2020)
      Flow curves of 15Kh2MFA, Sv 08Kh19N10G2B and 08Kh18N10T steels used for fabrication of WWER-440 nuclear reactor pressure vessel and core internals were obtained using the automated ball indentation (ABI) test technique and ...