Department of Nano Fusion Technology, Pusan National University, Miryang-si 627-706, Korea.
Advanced Analysis Center, Korea Institute of Science and Technology, Cheongryang, P.O. Box 131, Seoul, Korea.
J Nanosci Nanotechnol. 2019 Oct 1;19(10):6487-6492. doi: 10.1166/jnn.2019.17071.
Although deformation and aging treatments of Cu-3 wt%Ti alloys dramatically enhance their mechanical properties, the corrosion behavior of ultra-fine grained (UFG) Cu-3 wt%Ti alloys produced by a combination of hot rolling and artificial aging has not been extensively explored yet. To bridge this gap, we herein probe the corrosion behavior of an UFG Cu-3 wt%Ti alloy produced by cold rolling and artificial aging, revealing that cast sample corrosion preferentially occurs around the -Cu₄Ti phase. Compared to that of the coarse-grained Cu-3 wt%Ti alloy, the corrosion resistance of its UFG counterpart is remarkably higher, which is ascribed to the effects of grain refinement and enveloping between the -Cu matrix and -Cu₄Ti in the absence of pitting corrosion. The development of ultra-fine microstructure upon the introduction of severe deformation is shown to dramatically improve the corrosion resistance of aging-hardened Cu-3 wt%Ti alloys without sacrificing their mechanical properties. Finally, we demonstrate that solid solution treatment of the Cu-3 wt%Ti alloy results in serious mechanical property deterioration, even though the thus treated samples feature the lowest corrosion current density.
尽管 Cu-3wt%Ti 合金的变形和时效处理显著提高了其力学性能，但通过热轧和人工时效相结合生产的超细晶（UFG）Cu-3wt%Ti 合金的腐蚀行为尚未得到广泛研究。为了弥补这一空白，我们研究了冷轧和人工时效生产的 UFG Cu-3wt%Ti 合金的腐蚀行为，结果表明铸态样品的腐蚀优先发生在 -Cu₄Ti 相周围。与粗晶 Cu-3wt%Ti 合金相比，其 UFG 对应物的耐腐蚀性显著提高，这归因于晶粒细化和 -Cu 基体与 -Cu₄Ti 之间的包络作用，而没有点蚀腐蚀。严重变形引入的超细微观结构的发展表明，在不牺牲力学性能的情况下，时效硬化的 Cu-3wt%Ti 合金的耐腐蚀性得到了显著提高。最后，我们证明了 Cu-3wt%Ti 合金的固溶处理会导致严重的力学性能恶化，即使经过处理的样品具有最低的腐蚀电流密度。
