Combining thermo-photo elasticity for analysis of cracked bodies

• Published in: Journal of Optoelectronics and Advanced Materials Vol. 10; no. 11; pp. 2876 - 2881
• Main Authors: Marsavina, L, Craciui, E M, Tomlinson, R A
• Format: Journal Article
• Language: English
• Published: 01.11.2008
• ISSN: 1454-4164

In recent years the possibility of using experimental stress analysis techniques like thermoelastic and photoelastic for determining the fracture mechanics parameters in cracked bodies has been highlighted. This has the advantage that photoelastic and thermoelastic measurements can be performed simultaneously. It is proposed that if both thermo- and photo- elastic data were taken simultaneously from the same crack and the stress intensity factor determined by the two different techniques then confidence could be obtained in the results. Such a procedure would have use where no analytical solution was available for verification purposes. An experiment was carried out to assess the potential and accuracy of using photo and thermo elastic stress analysis to determine the stress intensity factors. A central notch was machined into a steel cruciform specimen and a polymer coating was bonded adjacent to one end of the notch. The specimen was loaded in a biaxial test machine, thermoelastic and photoelastic data were recorded from the coating and stress intensity factors determined. This paper presents some results of the mixed mode stress intensity factors obtained by photoelasticity and thermo-elasticity for a sharp notch in the biaxial specimen.