On the intermetallic constituents in the sodium-induced edge cracking of hot-rolled AA5182 aluminum alloys

The productivity and recovery of hot-rolled Al-Mg-Mn sheets often suffer from sodium-induced edge cracking. In this study, AA5182 ingots with different levels Na were prepared by direct-chill (DC) casting, then subsequently subjected to homogenisation hot-rolling processes. crack occurrence during hot rolling in the pass #11 (84% reduction) #18 (96% was investigated, special attention paid impact intermetallic constituents ingot subsurface region, where all cracks initiated. Correlations between susceptibility cracking, enriched inverse segregation zone, Mg2Si cavitation, meniscus bands, contamination observed. results revealed that Fe-rich particles not involved formation, while had a strong tendency debond Al matrix form cavities at edges rolled strip. higher content, more severe consequently, Numerous debonded contaminated region provided favourable conditions for initiation propagation. role bands on large profound also elaborated.