喷丸强化与固溶强化复合处理对2024铝合金耐蚀性能的影响

Effects of shot peen strengthening and solution strengthening combined treatment on corrosion resistance of 2024 aluminum alloy

研究了喷丸强化、固溶强化、喷丸强化+固溶强化3种工艺对初始时效态2024铝合金耐盐雾腐蚀性能的影响。结果表明,原始试样组织内存在大量第二相颗粒,颗粒尺寸最长约为83μm。经固溶处理后,部分第二颗粒溶解于基体,剩余颗粒尺寸减小至17μm。采用喷丸强化和固溶强化复合处理后,材料近表面组织的第二相颗粒几乎全部溶解。当盐雾腐蚀时间为3 h时,原始试样的腐蚀坑直径约为?90μm,喷丸+固溶强化试样的腐蚀坑直径约为?50μm;喷丸试样的腐蚀深度约为38.75μm,而喷丸+固溶强化试样的腐蚀深度降低至12.5μm。这表明喷丸强化和固溶强化复合处理有助于第二相颗粒的溶解,改善材料组织和成分的均匀性,进而提升铝合金的耐蚀性能。

Effects of shot peening strengthening,solution strengthening and shot peening strengthening+solution strengthening on the salt spray corrosion resistance of as⁃aged 2024 aluminum alloy were studied.The results show that there are numerous secondary phase particles in the primitive specimen microstructure,with the longest particle size of about 83μm.After solution treatment,some of the secondary phase particles dissolve in the matrix,and the remained particle size is reduced to 17μm.After the combined treatment of shot peening and solution treatment strengthening,almost all of the secondary phase particles near the surface are dissolved.When the salt spray corrosion test time is 3 h,the diameter of the corrosion pit of the primitive specimen is approximatelyϕ90μm,the corrosion pit diameter of the shot peening and solution strengthened specimen is aboutϕ50μm,the corrosion depth of the shot peening specimen is about 38.75μm,while the corrosion depth of the shot peening and solution strengthened specimen decreases to 12.5μm.This indicates that the combined treatment of shot peening and solution treatment strengthening contributes to dissolve the second phase particles,improves the uniformity of material structure and composition,and thereby enhances the corrosion resistance of aluminum alloys.