Prezentace na mezinárodní konferenci QIRT 18

15.08.2018
Ve dnech 25. - 29. června 2018 proběhla v Berlíně 14. mezinárodní konference Quantitative InfraRed Thermography. Konference se zúčastnili Michal Švantner a Jiří Tesař s příspěvky:

Thermographic detection of damage initiation of cyclically loaded parts

M. Švantner*, J. Skála*, L. Muzika*, P. Čížek**
* University of West Bohemia, Univerzitní 8, 30614 Plzen, Czech Republic, msvantne@ntc.zcu.cz
** MATERIÁLOVÝ A METALURGICKÝ VÝZKUM, Pohraniční 693/31, 703 00 Ostrava- Vítkovice, Czech Republic, petr.cizek@mmvyzkum.cz

Abstract

The contribution is focused on thermographic detection of initiation of plastic deformation and damage of cyclically loaded parts. Plastic deformation of material is connected with heat generation, which can be utilized for thermographic inspection. Location of critical parts and initiation time can so be detected at different technological tests before damage. A procedure for highlighting of an indication based on Fast Fourier Transform is introduced in the contribution. Procedure and results of thermographic inspection of cyclically loaded physical model of welded pipes are presented.

Infrared thermography online 1D and offline 2D evaluation of mechanical properties at cycling fatigue testing

J. Tesař*, M. Švantner*, J. Skála*, M. Novák**
* University of West Bohemia, New Technologies – Research Center, Univerzitní 8, Plzeň, Czech Republic, tesar@ntc.zcu.cz, msvantne@ntc.zcu.cz, jskala@ntc.zcu.cz
** Research and Testing Institute Plzeň, Plzeň, Czech Republic, novak@vzuplzen.cz

Abstract

Mechanical testing and cyclic fatigue testing belong to the important material examinations. Standard methods are demanding to time and number of identical samples is needed. Thermographic methods have ambitions to shorten the testing time using only a few samples undergoing cyclic loading. A stepwise cyclic loading was applied to two cylindrical samples from 15Ch2NMFA steel. The temperature of tested samples was measured during the testing with increasing loading force using infrared camera. An online 1D and offline 2D evaluation of fatigue limit is introduced in this contribution. The results of fatigue limit evaluated with standard method and thermographic methods (1D and 2D) are compared and proved good agreement between methods.