(1. 江蘇大學(xué) 材料科學(xué)與工程學(xué)院，鎮(zhèn)江 212013；
2. 江蘇大學(xué) 江蘇省高端結(jié)構(gòu)材料重點(diǎn)實(shí)驗室，鎮(zhèn)江 212013)
摘 要: 采用50%搭接率不同冷卻方式的多道搭接攪拌摩擦加工技術(shù)，對厚度為4 mm的6061鋁合金板材進(jìn)行改性加工。通過拉伸試驗、維氏硬度試驗、晶間腐蝕試驗、金相顯微鏡、掃描電鏡和透射電鏡等分析加工區(qū)域材料的力學(xué)性能、晶間腐蝕性能和顯微組織。結(jié)果表明：多道次水冷攪拌摩擦加工晶粒細(xì)化最顯著，得到超細(xì)晶組織；相比于空冷攪拌摩擦加工，水冷可明顯減小加工區(qū)的軟化程度；在滿足力學(xué)性能的基礎(chǔ)上，母材經(jīng)多道次水冷攪拌摩擦加工后，耐晶間腐蝕性能有了顯著提高。
關(guān)鍵字: 6061鋁合金；攪拌摩擦加工；再結(jié)晶；力學(xué)性能；晶間腐蝕
（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
