doc. Ing. Václav Pouchlý, Ph.D., Ing.Paed.IGIP
E-mail:   pouchly@fme.vutbr.cz  Dept.:   Institute of Materials Science and Engineering Dept. of Ceramics and Polymers Position:   Associate Professor Room:   A4/104

Supervised courses:

• Bachelor Seminar (B-MTI) (FEM)
• Diploma Seminar (M-MTI) (WD6)
• Materials Selection and Performance (WUV-A)

Publications:

• POUCHLÝ, V.; MACA, K.; SHEN, Z.:
  Two-stage master sintering curve applied to two-step sintering of oxide ceramics,
  Journal of the European Ceramic Society, Vol.33, (2013), No.12, pp.2275-2283, ISSN 0955-2219
  journal article - other
• POUCHLÝ, V.; MACA, K.; XIONG, Y.; SHEN, Z.:
  Master Sintering Surface – A Practical Approach to Its Construction and Utilization for Spark Plasma Sintering Prediction,
  Science of Sintering, Vol.44, (2012), No.2, pp.169-175, ISSN 0350-820X, International Institute for the Science of Sintering
  journal article - other
• XIONG, Y.; HU, J.; SHEN, Z.; POUCHLÝ, V.; MACA, K.:
  Preparation of Transparent Nanoceramics by Suppressing Pore Coalescence, WILEY-BLACKWELL
  journal article in Web of Science
• POUCHLÝ, V.; MACA, K.:
  Master Sintering Curve - A Practical Approach to its Construction, International Institute for the Science of Sintering
  journal article in Web of Science
• MACA, K.; POUCHLÝ, V.; ŽALUD, P.:
  Two-Step Sintering of Oxide Ceramics with Various Crystal Structures, Elsevier
  journal article in Web of Science

List of publications at Portal BUT

Abstracts of most important papers:

• POUCHLÝ, V.; MACA, K.; SHEN, Z.:
  Two-stage master sintering curve applied to two-step sintering of oxide ceramics,
  Journal of the European Ceramic Society, Vol.33, (2013), No.12, pp.2275-2283, ISSN 0955-2219
  journal article - other
  Tetragonal (3 mol% Y2O3) and two cubic zirconia (8 mol% Y2O3) as well as alumina green bodies were used for the construction of the Master Sintering Curve (MSC) created from sets of constant-rate-of-heating (CRH) sintering experiments. The activation energies calculated according to the MSC theory were 770 kJ/mol for Al2O3, 1270 kJ/mol for t-ZrO2, 620 kJ/mol and 750 kJ/mol for c-ZrO2. These values were verified by an alternative approach based on an analysis of the densification rate in the intermediate sintering stage. The MSCs established from the Two-Step Sintering (TSS) experiments showed at high densities a significant deflection from those constructed from the CRH experiments. This deflection was explained by lower sintering activation energy in the closed porosity stage. A new two-stage MSC model was developed to reflect the change in sintering activation energy and to describe TSS. The efficiency of TSS of four materials under investigation was correlated with their activation energies during the final sintering stage.
• POUCHLÝ, V.; MACA, K.; XIONG, Y.; SHEN, Z.:
  Master Sintering Surface – A Practical Approach to Its Construction and Utilization for Spark Plasma Sintering Prediction,
  Science of Sintering, Vol.44, (2012), No.2, pp.169-175, ISSN 0350-820X, International Institute for the Science of Sintering
  journal article - other
  The sintering is a complex thermally activated process, thus any prediction of sintering behaviour is very welcome not only for industrial purposes. Presented paper shows the possibility of densification prediction based on concept of Master Sintering Surface (MSS) for pressure assisted Spark Plasma Sintering (SPS). User friendly software for evaluation of the MSS is presented. The concept was used for densification prediction of alumina ceramics sintered by SPS.
• XIONG, Y.; HU, J.; SHEN, Z.; POUCHLÝ, V.; MACA, K.:
  Preparation of Transparent Nanoceramics by Suppressing Pore Coalescence, WILEY-BLACKWELL
  journal article in Web of Science
  Microstructural developments in nanoceramics were investigated in 3Y-TZP compacts with relative density (RD) exceeding 93%. Special attentions were paid to the evolutions of pore structures. It was found that the densification process of nanoceramic compacts with apparently close porosity was greatly jeopardized by pore coalescence. This observation was interpreted by the coalescence of locally interconnected pores originated from inhomogeneous packing of particles. The pore coalescence can be suppressed by application of an external pressure. The processing principle was demonstrated by spark plasma sintering (SPS) with extended holding at a minimized sintering temperature. The highly dense 3Y-TZP nanoceramics containing no large pores became optically transparent
• MACA, K.; POUCHLÝ, V.; ŽALUD, P.:
  Two-Step Sintering of Oxide Ceramics with Various Crystal Structures, Elsevier
  journal article in Web of Science
  The influence of Two-Step Sintering (TSS) process on the final microstructure of oxide ceramic materials with three different crystal structures was studied. Two kinds of alumina (particle size 100nm resp. 240nm) as well as tetragonal zirconia (stabilized with 3mol%Y2O3, particle size 60nm) and cubic zirconia (8mol%Y2O3, 140nm) powders were cold isostatically pressed and pressureless sintered with different heating schedules. The microstructures achieved with TSS method were compared with microstructures achieved with conventional Single-Step Sintering schedule (SSS). The results showed that the efficiency of the TSS of these oxide ceramics was more dependent on their crystal structure than on their particle size and green body microstructure. The method of TSS brought only negligible improvement of the microstructure of tetragonal zirconia and hexagonal alumina ceramics. On the other hand, TSS was successful in the sintering of cubic zirconia ceramics; it led to a decrease in grain size by a factor of 2.
• MACA, K.; POUCHLÝ, V.; SHEN, Z.:
  Two-Step Sintering and Spark Plasma Sintering of Al2O3, ZrO2 and SrTiO3 Ceramics,
  INTEGRATED FERROELECTRICS, Vol.99, (2008), No.1, pp.114-124, ISSN 1058-4587
  journal article - other
  The influence of Two Step Sintering and Spark Plasma Sintering processes on the microstructure of three kinds of oxide ceramics was studied. Al2O3 (with initial particle size of 240 nm), ZrO2 (60 nm, stabilized with 3 mol%Y2O3) and SrTiO3 (50 nm) powders were cold isostatically pressed and pressureless sintered with different heating regimes. It was found that the method of TSS does not bring about significant reduction of final grain size in Al2O3 and ZrO2 ceramics, but does reduce the grain size in perovskite SrTiO3 ceramics. Pressureless sintering of SrTiO3 leads only to 95%TD dense ceramics with the minimum grain size of 400 nm. In comparison, by SPS, with an applied uniaxial pressure of 200MPa, SrTiO3 ceramic of 98%TD dense with grain size of 80 nm was prepared.