挤压工艺对6061铝合金晶间腐蚀行为的影响机理研究

Research on the Mechanism of Extrusion Process Effects on Intergranular Corrosion Behavior of 6061 Aluminum Alloy

摘要

6061铝合金因比强度高、加工性与耐蚀性优良，被广泛应用于交通装备型材、建筑结构件及电子散热器等领域。但在挤压过程中，温度场、应力场及速度等因素共同作用，使组织形貌和晶界析出行为发生变化，导致晶间腐蚀敏感性提升。工程研究表明，挤压速度、挤压比、流动均匀性和出料温度直接影响晶界Mg₂Si相的连续性与贫化区宽度，从而改变服役耐蚀性能。基于对组织演变、析出行为与残余应力分布的分析，可通过优化温度区间、改善金属流动和平稳冷却，并与合理时效制度匹配，有效降低连续析出，提升6061铝合金型材的晶间腐蚀稳定性。

Abstract

6061 aluminum alloy, renowned for its high specific strength, excellent processability, and corrosion resistance, is widely used in transportation equipment profiles, architectural structural components, and electronic heat sinks. However, during extrusion, factors such as temperature field, stress field, and flow velocity collectively alter microstructure morphology and grain boundary precipitation behavior, thereby increasing intergranular corrosion sensitivity. Engineering studies indicate that extrusion speed, extrusion ratio, flow uniformity, and extrusion temperature directly influence the continuity of Mg₂Si phase at grain boundaries and the width of depletion zones, which in turn affects service corrosion resistance. Through analysis of microstructural evolution, precipitation behavior, and residual stress distribution, optimizing temperature ranges, improving metal flow and steady cooling, combined with appropriate aging regimes, can effectively reduce continuous precipitation and enhance intergranular corrosion stability of 6061 aluminum alloy profiles.

关键词

6061铝合金 / 挤压工艺 / 晶间腐蚀 / 晶界析出相 / 工业型材 / 组织控制

Key words

6061 aluminum alloy / extrusion process / intergranular corrosion / intergranular precipitates / industrial section / microstructure control

参考文献

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[2] 王文辉. 时效处理对6061铝合金力学性能及腐蚀行为的影响[D]. 宁夏大学, 2023.

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