People
Ing. Jan Šleichrt, Ph.D.

Ing. Jan Falta; Ing. Nela Krčmářová; Ing. Jan Šleichrt, Ph.D.

Flash X-ray system and high speed X-ray imaging methods will be used to investigate the internal processes in the materials during dynamic loading. The developed experimental equipment will be employed for investigation in field of modern materials for ballistic and impact protection, personal protective equipment or aerospace/space applications, e.g., sandwiches, composite panels and metamaterials, and to characterize their fundamental mechanical processes like failure and fracture behavior, wave propagation and constituent materials interaction. Significant part of research will be aimed on experimental investigation of materials filled with dilatant fluid. In this field, the combination of X-ray flash system with instrumented dynamic experiments can reveal crucial aspects of their deformation behavior. The outputs of the project will provide an important insight into deformation behavior and will serve as an important basis for reliable numerical modeling of the related problems and for relevant optimization schemes during design process of state-of-the-art materials. The goal of the project is experimental investigation of state-of-the-art materials during impacts

2022 - 2026

JUNIOR STAR

Ing. Marcel Adorna; Ing. Tomáš Doktor, Ph.D.; Ing. Jan Falta; Ing. Tomáš Fíla, Ph.D.; Ing. Michaela Jurko; doc. Ing. Petr Zlámal, Ph.D.; Ing. Jan Šleichrt, Ph.D.

The goal of the project is to develop and experimentally validate a new structural panel for energy absorption applications with unique properties based on polymeric cellular core and nanocrystalline metal coating. The strain-rate sensitivity of the strut material (polymeric foam and auxetic) will be achieved by micro inertia of the coated framework showing a stretching- induced additional amount of energy dissipation. Design optimization of such a structure requires in-deep investigation of the deformation behavior for the given specific impact conditions. Advanced numerical modelling will be performed at all structural levels, from cell wall mechanics up to whole panel behaviour. For this, a combination of several experimental methods (micro-CT, static compression, drop tests, SHPB and gas gun experiments) will be used. The experimental results will be used to validate our FE models describing the deformation behaviour at small to high velocity impacts. The project is building upon our previous experiences with numerical/experimental optimization of metal foams and auxetics.

2019 - 2021

Standard projects

prof. Ing. Ondřej Jiroušek, Ph.D.

The proposed project is aimed at measurement and description of the mechanical behaviour of advanced materials (cell materials, auxetic structures, composite materials, etc.) at medium and high deformation rates using the experimental SHPB setup and its modifications. The dependence of material characteristics on deformation velocity is a key parameter in the assessment of material properties, whether for use in transport applications - absorption of impact deformation energy (deformation zones) or for protection of critical infrastructure. The project focuses on the methodology of measuring complex structures that will be able to absorb large amounts of kinetic energy and designing penetration experiments of these structures. Analysis of material behaviour at the impact site of the impactor is very challenging, as the sample of the material makes optical recording of the deformation difficult for application of digital image correlation (DIC). The project proposal deals with a concept of measurement and methodology using radiographic methods for examination and description of deformation at the site of impact in co-operation with currently running OP VVV project (Excellent research, call 19). The project is focused on the application of a new OHPB method for determining the behaviour of materials at impact loads. Furthermore, the project focuses on investigation of the deformation behaviour of materials under impact loads using X-rays. The project will study the use of two OHPB variants and utilization of the X-rays for recording the penetration of a projectile through the studied material. The results of the experiments will be used to describe the behaviour of materials under extreme loads and to develop numerical methods for simulating these processes using the Finite Element Method. The project thematically follows the national GAČR (GA15-15480S) project focused on modifying the SHPB setup and ties upon the achieved results.

2018 - 2019

Studentská grantová soutěž ČVUT - SGS18/155/OHK2/2T/16

Ing. Tomáš Doktor, Ph.D.; Ing. Michaela Jurko; Ing. Nela Krčmářová; Ing. Jan Šleichrt, Ph.D.

Konference navazuje na tradici česko-německých bilaterálních symposií, kterou založili prof. Karl-Hans Laermann (někdejší spolkový ministr školství a výzkumu) s prof. Stanislavem Holým (jedním z nejvýznamnějších odborníků v oblasti experimentální mechaniky) v roce 1985. O rozvoj konference v následujících letech se významnou měrou zasloužil prof. Josef Jíra (bývalý děkan ČVUT FD). Cílem konference je setkání mladých vědeckých pracovníků, doktorandů a studentů z evropských univerzit a výzkumných center, prezentace výsledků jejich výzkumu, výměna zkušeností a navazování kontaktů. Výsledky jsou prezentovány formou přednášek s diskusí. Jednotlivé sekce budou uvedeny vyzvanými přednáškami předních odborníků (letos prof. M. Gutermann, prof. O. Jiroušek). Na základě diskuze nad řešenými tématy vznikají návrhy na mezinárodní výzkumné projekty nebo stáže jednotlivých účastníků. Všechny příspěvky projdou před publikováním standardním peer-review procesem, pro nemalou část účastníků prvním v jejich publikační činnosti. Sborník plných textů vyjde v rámci recenzovaného časopisu Acta Polytechnica CTU Proceedings, vydávaného nakladatelstvím ČVUT, který usiluje o zařazení do citační databáze Scopus. Tematické zaměření konferece zahrnuje zejména - Pokročilé experimentální metody mechaniky kontinua a mechaniky tekutin - Nedestruktivní zkoušení - Lomová mechanika, poruchy materiálu - Biomechanika - Hybridní numericko-experimentální metody - Problematika technologických procesů - Mikro- a nano- aplikace

2016 - 2016

Studentská vědecká konference ČVUT - SVK 48/16/F6

Ing. Tomáš Doktor, Ph.D.; Ing. Tomáš Fíla, Ph.D.; Ing. Petr Koudelka, Ph.D.; Ing. Jan Šleichrt, Ph.D.

The project is focused on investigation of time-dependent processes influencing mechanical properties and internal structure of advanced engineering materials. Combination of analytical, numerical and experimental methods will be used for determination of relations between mechanical properties and microstructure of studied materials. In the theoretical part analytical and numerical methods will be implemented and techniques for evaluation of effective quasi-static and dynamic response of the studied materials will be developed. Experimental methods will involve enhancement of applications for processing and evaluation of experiments and also design of specialized measurement devices. These methods will be suitable for optimisation of the usage of advanced materials with microstructure in transportation applications and their safe operation.

2015 - 2017

Studentská grantová soutěž ČVUT - SGS15/225/OHK2/3T/16