Intergranular corrosion resistance properties of 5083 aluminum alloy

The intergranular corrosion resistance properties of 5083 aluminum alloy were studied by metallographic examination, scanning electron microscopy and transmission electron microscopy, and the effect of ‘white bright stripe' on the properties of 5083 aluminum alloy and its formation reasons were discussed. The results show that the ‘white bright stripe' on the surface of 5083 aluminum alloy specimen after intergranular corrosion made its intergranular corrosion resistance better. Affected by the grain size, the corrosion rate of the same batch of aluminum alloy samples was different. The elongated fibrous grains on the sample were larger in size, and the precipitates at the grain boundary were relatively less, so the intergranular corrosion resistance was better. Because the Mg element was more likely to segregate on both sides of the 5083 aluminum alloy sample, the intergranular corrosion cracks on the sample tended to be shallow in the middle and deep on both sides, which also led to the shallow intergranular corrosion cracks of the sample with smaller corrosion rate. The intergranular corrosion cracks in the middle of the sample was the deepest.Under the combined effect of larger grain size and Mg element segregation to both sides of the sample, ‘white bright stripe' appeared on the 5083 aluminum alloy sample, which was a sign of good intergranular corrosion resistance.