| dc.description.abstract | This study explored the effects of Fe and Mn on the recrystallization, mechanical properties and corrosivity of Al-5.0Mg forged aluminum alloy by microstructure observation, annealing treatment at different temperatures for corrosion properties, and mechanical property tests.
The results show that as the Fe content in the alloy increases, the iron-rich phase that is easy to accumulate during processing will also increase, and the alloy recrystallization rate will increase after annealing, which will coarsen the grains and damage the strength of the alloy. In addition, the iron-rich phase has also been found to have an adverse effect on ductility. As the Mn content increases, fine Al6Mn particles will be produced in the alloy grains. Al6Mn can block the shift and grain boundary movement during annealing, inhibit the alloy recrystallization, and then refine the grains to achieve the effect of fine grain strengthening. In addition, The fine Al6Mn itself also has the effect of dispersion strengthening, which makes the alloy strength increase significantly.
In addition, as the Mn content increases, the alloy grain size decreases, and the β phase (Mg2Al3) will change from discontinuous to continuous precipitation at the grain boundary, thus impairing the corrosion resistance of the alloy; and as the Fe content increases, the low Mn alloy grain size may be fine.The grain size of the high Mn alloy will be refined, and there will be no significant difference in the grain size of the high Mn alloy, indicating that Fe has no positive effect on the corrosion resistance of the alloy.
Based on the above results, it is found that alloys containing high Mn and low Fe have the best mechanical properties and the finest grain size, but poor corrosion resistance, while alloys containing low Mn and low Fe have poor mechanical properties and the coarsest grain size , but have the best corrosion resistance. | en_US |