Laser Cladding as a Repair Technology for Aircraft Components - Corrosion and Fatigue Implications

Q. Liu ¹, B. Hinton ², M. Brandt ³, W. Neil ¹, A. Wythe ¹, K Sharp ¹.

1. DSTO Melbourne, 2. RMIT University,  Melbourne 3. Monash University, Melbourne, Australia

Abstract: The laser cladding (LC) process offers a cost saving, repair alternative to mechanically fastened doublers or the replacement of damaged components due to its relatively low heat input, flexibility, high variety of filler materials and ease of automation. LC involves using a scanning high-powered laser beam to melt the filler powder and a thin layer of the substrate, to form a non-porous well bonded coating. Recent laser technology advances have made laser cladding a viable technology for the repair of high strength aluminium alloy aircraft components.  This paper reports on the corrosion behaviour under constant immersion conditions and atmospheric exposure of Al-Si alloy layers deposited on an AA 7075 aluminium alloy substrate by a laser cladding process. The effects of changes to the microstructure of the alloy by the cladding process on the corrosion resistance and fatigue properties will be discussed. The paper will also outline the processes required in order to certify the technology for use on Australian Defence Force military aircraft.