Crack repair of SENT specimen using the interference fit process

This attempt aims at investigating the Interference Fit Process as a procedure to arrest a detectable crack size in mechanical part. The 7075-T6 Aluminum alloy cracked SENT specimen is considered in the current work. A 2D- FE analysis is implemented to simulate the stress distribution around the expanded hole after Interference Fit Process. Lemaitre-Chaboche model was considered for describing the material behaviour. Both, fatigue life improvement and compressive residual stress distribution, arising from the Interference Fit Process, are predicted. Different crack lengths, different interference fit sizes and different crack arrest hole (CAH) diameters are investigated. In order to optimize the Interference Fit Technique's process parameters and study their effects and their interactions, the Response Surface Methodology (RSM) is implemented. Results show that higher fatigue life improvement is obtained at hole diameter equal to 6 mm, an Interference Fit Size equal to 0.2 mm and an initial crack size equal to 20 mm. The Design of Experiments (DoE) procedure can be used with the Interference Fit Process as an efficient tool to ensure the safety behaviour of cracked components.