Magnesium, due to its unique mechanical properties and natural availability, holds significant potential for engineering applications. Furthermore, through alloying, its properties can be further enhanced. In magnesium alloys, these include low density, a favorable weight-to-strength ratio, and good machinability. The AZ80 alloy is a commonly used material in engineering applications, with its main alloying elements being aluminum, manganese, and zinc, which is the subject of investigation in this task. It was solution heattreated (at 420°C for 24 hours), and samples for examination were cut from drawn rod billets. All four samples underwent laser shock peening, with two of them also subjected to prior precipitation hardening (8 hours at 250°C). The laser processing conditions were identical except for differences in pulse density (178 and 400 pulses/cm²). The analysis included an examination of microstructure, topography, roughness, microhardness, residual stresses, corrosion resistance, and a comparison with the base material.
Surface roughness increased due to laser processing, with grain refinement observed in the upper surface layer, along with higher microhardness and compressive residual stresses. Precipitation hardening had a significant effect on corrosion, as these samples, unlike those in the base condition, did not show a decrease in corrosion potential over time. Moreover, the corrosion rate was much lower, and material repassivation was improved. However, the stability of the surface film was somewhat reduced.
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