A three-point electrical potential difference method for in situ monitoring of propagating mixed-mode cracks at high temperature

In this paper an electrical potential difference method for the real-time assessment of both the length and the direction of Mode II cracks is presented. Three measuring electrodes are placed in selected positions over the gauge area of a specially designed shear specimen and their readings are associated with the actual position of the crack tip using Finite Element Analysis (FEA). This information can be processed in real-time to provide continuous monitoring of the crack as it propagates either in pure Mode II (in-plane shear) or mixed Mode I (tension) and Mode II if the inclination of the crack exceeds 20. In fatigue testing it is pos

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