Jana Dvořáková

Jana Dvořáková

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 October 2020 in Materials
Verified
Journal Article
Open access
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ZHZdenek Horak
Zdenek Horak
KDKarel Dvorak
Karel Dvorak
LZLucie Zarybnicka
Lucie Zarybnicka
HVHana Vojackova
Hana Vojackova
JDJana Dvořáková
Jana Dvořáková
MVMiloslav Vilimek
Miloslav Vilimek
Rigid polyurethane (PUR) foam is products used as a biomedical material for medical device testing. Thermal stability is a very important parameter for evaluating the feasibility of use for testing surgical instrument load during drilling. This work aimed to perform experimental measurements to determine the dependence of the mechanical properties of a certified PUR on temperature, strain rate and density. Experimental measurements were realised for three types of the PUR samples with different density 10, 25 and 40 pounds per cubic foot. The samples were characterised in terms of their mechanical properties evaluated from tensile and compression tests at temperatures of 25 °C, 90 °C and 155 °C. Furthermore, the structures of the samples were characterised using optical microscope, their thermal properties were characterised by thermogravimetric analysis, and their density and stiffness with the effect of temperature was monitored. The results show that it is optimal not only for mechanical testing but also for testing surgical instruments that generate heat during machining. On the basis of experimental measurements and evaluations of the obtained values, the tested materials are suitable for mechanical testing of medical devices. At the same time, this material is also suitable for testing surgical instruments that generate heat during machining.

6 December 2021 in Materials
Verified
Journal Article
Open access
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KDKarel Dvorak
Karel Dvorak
JDJana Dvořáková
Jana Dvořáková
LZLucie Zarybnicka
Lucie Zarybnicka
ZHZdenek Horak
Zdenek Horak
The presented text deals with research into the influence of the printing layers’ orientation on crack propagation in an AlSi10Mg material specimen, produced by additive technology, using the Direct Metal Laser Sintering (DMLS) method. It is a method based on sintering and melting layers of powder material using a laser beam. The material specimen is presented as a Compact Tension test specimen and is printed in four different defined orientations (topology) of the printing layers—0°, 45°, 90°, and twice 90°. The normalized specimen is loaded cyclically, where the crack length is measured and recorded, and at the same time, the crack growth rate is determined. The evaluation of the experiment shows an apparent influence of the topology, which is essential especially for possible use in the design and technical preparation of the production of real machine parts in industrial practice. Simultaneously with the measurement results, other influencing factors are listed, especially product postprocessing and the measurement method used. The hypothesis of crack propagation using Computer Aided Engineering/Finite Element Method (CAE/FEM) simulation is also stated here based on the achieved results.

30 November 2023 in Metals
Verified
Journal Article
Open access
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KDKarel Dvorak
Karel Dvorak
JDJana Dvořáková
Jana Dvořáková
DMDušan Majtás
Dušan Majtás
RŠRadek Ševčík
Radek Ševčík
LZLucie Zarybnicka
Lucie Zarybnicka
Application deployment of 3D-printed products represents a progressive area of industrial use of specific metal alloys. In parallel with starting points based on mechanical characteristics in the static and cyclic areas, dilation behavior is an important parameter. A typical application is, for example, components in the aerospace sector, where the components are exposed for a short period to a significant temperature difference in both positive and negative values. Current industrial trends lead to the deployment of additive technologies for producing aircraft system components and instrument parts. Testing of AlSi10Mg alloy samples prepared by direct metal laser sintering, in the past DMLS, now according to the standard laser powder bed fusion (PBF-LB/M) method, is carried out by measuring dilation during a controlled temperature course. The AlSi10Mg alloy is used for mechanically less stressed components, from which a high accuracy of functional dimensions is usually required, which can be affected by dilation characteristics in a wide temperature range. Additively produced components have different dilation characteristics within an identical alloy, often dependent on the production method and orientation during 3D printing. The article presents the testing results and subsequent application characteristics of an additively produced aluminum alloy, considering dilation characteristics.

2 July 2024 in Metals
Verified
Journal Article
Open access
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KDKarel Dvorak
Karel Dvorak
JDJana Dvořáková
Jana Dvořáková
DMDušan Majtás
Dušan Majtás
RŠRadek Ševčík
Radek Ševčík
LZLucie Zarybnicka
Lucie Zarybnicka
Titanium-based alloys are a widely applicable engineering material with high strength, low weight, non-magnetic, and corrosion resistance. At the same time, resistance to low temperatures is declared, which offers the material’s applicability for, e.g., aircraft or ship technology. Additive technologies are part of the industrial spectrum of material processing, especially the Laser Powder Bed Fusion of Metals method for metal alloys, which creates a layered structure of the resulting body. The topology of the internal structure, in relation to the temperature history of the functional environment, influences thermal expansion and the associated functional characteristics. Knowledge of the thermal expansion of printed strength and non-strength functional components and accessories is essential for future applications, especially in environments with high repeatable temperature changes, such as the aerospace industry. This paper presents the results of testing the expansion, mechanical, microstructural, and mineralogical characteristics of Ti6Al4V over the temperature range of −70 to 60 °C using a combination of instrumental techniques such as X-ray diffraction and nanoindentation. It was found that the topological orientations of the printed samples directly influenced the tested properties, e.g., the coefficient of thermal expansion in the direction perpendicular to the printed layers showed approximately 12% lower value compared to the other directions. Due to the progression of the application of the manufacturing method and its applicability within selected industries, the research provides results in a new area, which is supported by the relevant research.

25 April 2026 in Journal of Building Engineering
Verified
Journal Article
Open access
Libor TopolářLibor Topolář
Libor Topolář
LPLubos Pazdera
Lubos Pazdera
KDKarel Dvorak
Karel Dvorak
FČFelix Černý
Felix Černý
JDJana Dvořáková
Jana Dvořáková
Oldrich SuchardaOldrich Sucharda
Oldrich Sucharda

3 March 2026
Verified
Book Chapter
Open access
KDKarel Dvorak
Karel Dvorak
JDJana Dvořáková
Jana Dvořáková
Additive components manufacturing with a wide range of applications represents a progressive technological segment in piece, small batch, and series production. The importance is evident in small series of shape and dimension specific components. A typical area comprises components for the application of less widespread activities. In general, these are parts with low levels of mechanical stress. The advantage of additive technologies is the rapid production preparation of shape-complex components based on a digital model. The operational specificity of aircraft components is the temperature range of the application environment and the associated expected mechanical characteristics. The present paper shows the mechanical testing results of composite, additively manufactured materials in a wide temperature range.