Infrared Image Processing for the Calorimetric Analysis of Fatigue Phenomena

• Published in: Experimental mechanics Vol. 48; no. 1; pp. 79 - 90
• Main Authors: Berthel, B., Chrysochoos, A., Wattrisse, B., Galtier, A.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.02.2008; Springer; Society for Experimental Mechanics
• Subjects: Biomedical Engineering and Bioengineering; Characterization and Evaluation of Materials; Control; Dynamical Systems; Engineering; Engineering Sciences; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Lasers; Materials and structures in mechanics; Measurement and testing methods; Mechanics; Optical Devices; Optics; Photonics; Physics; Solid Mechanics; Static elasticity (thermoelasticity...); Structural and continuum mechanics; Vibration; Fatigue; Thermoelasticity; Steel; Dissipation; Infrared imaging; Infrared thermography; Temperature distribution; Heat treatment; Heat equation; Image processing; Infrared imaging, Steel; Thermomechanical properties; Modeling; Heat source; Fatigue test; Thermal imaging; Dual phase steel
• ISSN: 0014-4851; 1741-2765
• DOI: 10.1007/s11340-007-9092-2

This paper presents an infrared image processing procedure that was developed to study calorific effects accompanying material fatigue. This method enables us to separately estimate patterns of thermoelastic and dissipative sources. Heat sources were estimated on the basis of partial derivative operators present in a local form of the heat equation by using a set of approximation functions that locally fits the temperature field and takes the spectral properties of the sought sources into account. Numerical examples were used to check the validity of the method and to highlight its capabilities along with its limits. The paper concludes with examples of thermal image processing extracted from fatigue tests performed on a dual-phase steel. The coupling sources were compared to the theoretical predictions induced by a basic thermoelastic model, while the heterogeneous character of the fatigue development was highlighted in terms of dissipation sources.