A STUDY OF THE FLUORINE CORROSION OF THE AL-7075 ALLOY USING NUCLEAR TECHNIQUES

Two nuclear techniques, resonant nuclear reaction (RNR) and Rutherford backscattering (RBS), plus SEM, were used to study the corrosion of a luminum 7075 exposed to fluorine gas at 300-degrees-C for 60 to 300 h. An initial surface fluorine-rich layer is formed, growing gradually w ith time of exposure up to 80 h. This is followed by the formation of a subsequent inner AlF3 layer which is subject to strong mechanical st resses and starts to crack, losing its protective character.