scholarly journals Instrumental Configuration of Electromagnetic Thermography and Optical Thermography

Author(s):  
Haoran Li ◽  
Yuming Zhang ◽  
Shunyao Wu ◽  
Bin Gao ◽  
Guiyun Tian ◽  
...  

Electromagnetic thermography and optical thermography are both important non-destructive testing (NDT) methods that have been widely used in the fields of modern aerospace, renewable energy, nuclear industry, etc. The excitation modes are crucial whose performances have a decisive effect on the detection results. Previous studies mainly focused on the physics mechanism, applications, and signal processing algorithms. However, the instrument configuration is rarely presented. This paper is to introduces the recently designed excitation sources of electromagnetic thermography and optical thermography detection systems, respectively. These instruments involved L-shaped and Shuttle-shaped sensor structures for electromagnetic thermography and multi-modes excitation for optical thermography. Besides, the topologies and operating principles are shown in detail. Experimental results are carried out to verify the practicability and reliability of the proposed systems.

2018 ◽  
Vol 170 ◽  
pp. 03005 ◽  
Author(s):  
P. Kauffmann ◽  
M.-A. Ploix ◽  
J.-F. Chaix ◽  
C. Gueudré ◽  
G. Corneloup ◽  
...  

The inspection and control of sodium-cooled fast reactors (SFR) is a major issue for the nuclear industry. Ultrasonic solutions are under study because of the opacity of liquid sodium. In this paper, the use of leaky Lamb waves is considered for non-destructive testing (NDT) on parallel and immersed structures assimilated as plates. The first phase of our approach involved studying the propagation properties of leaky Lamb waves. Equations that model the propagation of Lamb waves in an immersed plate were solved numerically. The phase velocity can be experimentally measured using a two dimensional Fourier transform. The group velocity can be experimentally measured using a short-time Fourier transform technique. Attenuation of leaky Lamb waves is mostly due to the re-emission of energy into the surrounding fluid, and it can be measured by these two techniques.


Author(s):  
George M. Lloyd ◽  
Gu Hua ◽  
Ming L. Wang

Interdigitated surface and guided-wave transducers have only recently received attention as possible tools for non-destructive testing. This may be due in part to the increasing attention being paid to piezoelectric polymers as practical transduction materials for structural sensing and actuation. However, much remains to be done to produce a rugged, monolithic device oriented toward these sorts of applications, to characterize and optimize its passive and active response, to develop excitation strategies and signal processing algorithms that in tandem can be employed for arrayed structure monitoring applications. In this paper we confine ourselves to the first two topics and report on the development and proof-of-principle testing of a monolithic interdigitated polyvinyldine fluoride (PVDF) transducer. Specifically, we report on the design and response of an interdigitated transducer with relatively large finger spacings. The finger spacing yield measureable responses in the asymptotically slow single-mode region of Lamb wave dispersion behavior for frequency-thickness products which may be useful for nondestructive testing of many mechanical and civil structural systems.


2021 ◽  
pp. 63-70
Author(s):  
С.Е. Черных ◽  
В.Н. Костин ◽  
Ю.И. Комоликов

The possibility of testing the surface oxidation of zirconium has been investigated by the method of one-way active thermal non-destructive testing based on the analysis of radiation temperatures. The emissivity of the oxidized surface of zirconium samples obtained at different annealing temperatures was estimated at various stages and heating temperatures in the infrared wavelength range. It is shown that there is a principal possibility to remotely test the oxidation process of zirconium alloys used in the nuclear industry for the manufacture of fuel elements operating in the core of nuclear reactors.


Sign in / Sign up

Export Citation Format

Share Document