Effect of cryogenic treatment on corrosion resistance of AZ61 magnesium alloy welded joint

The welding test of 7mm thick AZ61 magnesium alloy plate was carried out by MIG welding; the joint was cryogenically treated at -180℃, and the holding time was 4h, 8h and 12h respectively; Weight loss method and electrochemical method were used to test the influence of cryogenic treatment on the corrosion resistance of welded joints before and after cryogenic treatment, and the corrosion morphology of specimens was observed by SEM. The test results show that the corrosion resistance of the joint sample reaches the best when the cryogenic treatment temperature is -180℃ and the holding time is 8h.