Effect of cold-working on corrosion induced damage in lug joints

Abstract

Lug joints are preferred joineries for transferring heavy loads to parent components in aerospace vehicles. They experience corrosion due to environmental conditions, improper surface finishes and rubbing displacement between the pin and lug-hole. This causes damage of different sizes and shapes near the lug-hole. Stiffness degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress analysis. The effect of this pit on fatigue crack initiation life is estimated. Lug-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked lug-hole. Numerical analysis is performed on this lug joint with press-fit. The results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

Keywords

• Lug joint
• Corrosion
• Crack initiation
• Cold-working
• Structural integrity