(1. 江苏大学 材料科学与工程学院,镇江 212013;
2. 江苏大学 江苏省高端结构材料重点实验室,镇江 212013)
摘 要: 采用50%搭接率不同冷却方式的多道搭接搅拌摩擦加工技术,对厚度为4 mm的6061铝合金板材进行改性加工。通过拉伸试验、维氏硬度试验、晶间腐蚀试验、金相显微镜、扫描电镜和透射电镜等分析加工区域材料的力学性能、晶间腐蚀性能和显微组织。结果表明:多道次水冷搅拌摩擦加工晶粒细化最显著,得到超细晶组织;相比于空冷搅拌摩擦加工,水冷可明显减小加工区的软化程度;在满足力学性能的基础上,母材经多道次水冷搅拌摩擦加工后,耐晶间腐蚀性能有了显著提高。
关键字: 6061铝合金;搅拌摩擦加工;再结晶;力学性能;晶间腐蚀
(1. School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China;
2. Jiangsu Province Key Laboratory of High-end Structural Materials, Jiangsu University, Zhenjiang 212013, China)
Abstract:The 6061 aluminium alloy was modified by multi-pass friction stir process (FSP) by different cooling methods at overlapping percentage of 50%. The mechanical properties, intergranular corrosion behavior and microstructure of processed zone were investigated by tensile test, vickers hardness test, intergranular corrosion test, optical microscopy, SEM and TEM observation. The results show that grain refinement is the most effective by multi-pass FSP by water cooling and the ultrafine-grained microstructure is obtained. Comparing to FSP with air cooling, water cooling can significantly reduce softening degree in stirred zones. On the basis of ensuring mechanical properties, the resistance of intergranular corrosion is better by multi-pass FSP with water cooling.
Key words: 6061 aluminium alloy; friction stir process; recrystallization; mechanical property; intergranular corrosion