Galvanic Corrosion of Al-Li Alloys Coupled to CFRP Composite

The use of carbon fiber reinforced polymer (CFRP) in the aerospace industry has increased over the past few decades. A new generation of aluminum-lithium (Al-Li) alloys, with improved corrosion resistance and other properties, are also being used on new aircraft. Due to the difference between the corrosion potential of carbon fibers and those of aluminum alloys, the galvanic interaction between aluminum alloys and CFRP needs to be evaluated. In this work, the galvanic corrosion performance of new Al-Li alloys and conventional aluminum alloys coupled to CFRP was evaluated in selected lab accelerated tests and outdoor exposure, using Al-CFRP mock-up panels. The results from this study indicate that Al-Li alloys have better galvanic corrosion performance in contact with CFRP, relative to the incumbent alloys.