藉由微結構觀察、ASTM G67硝酸腐蝕重量損失測試及機械性質測試（硬度、拉伸），探討微量鋯與安定化退火對Al-4.7Mg-0.75Mn (AA5383)合金腐蝕與機械性質之影響，結果顯示，不論是否含微量鋯之Al-4.7Mg-0.75Mn合金，於220℃下進行安定化退火熱處理，合金均會發生沿晶腐蝕敏感現象；但當安定化退火溫度升高至250℃時，雖然合金之機械強度會下降，但均無沿晶腐蝕敏感問題；且經250℃安定化退火之含鋯合金機械性質（UTS=348MPa、YS=254MPa、EL=12.0%）優於經220℃安定化退火之未含鋯合金（UTS=337MPa、YS=250MPa、EL=9.5%），也就是說藉由微量鋯的添加與適當的安定化熱處理，可以獲得兼具良好抗蝕能力與機械性質之Al-4.7Mg-0.75Mn合金。;Effect of minor zirconium addition and stabilizing annealing on the corrosion and mechanical properties of Al-4.7Mg-0.75Mn alloys were studied by analysing the microstructure, mechanical properties and the Nitric Acid Mass Loss Test (NAMLT). The results indicated that the intergranular corrosion (IGC) occurred no matter Al-4.7Mg-0.75Mn alloys contains zirconium or not after stabilizing annealing at 220℃. However, it is non-IGC if raising the stabilizing annealing temperature to 250℃. Furthermore, the alloy contains zirconium with a stabilizing annealing at 250℃ has better mechanical properties (UTS=348MPa, YS=254MPa, EL=12.0%) than the alloy without zirconium which stabilizing annealing at 220℃(UTS=337MPa, YS=250MPa, EL=9.5%). The Al-4.7Mg-0.75Mn alloy with minor zirconium addition as well as a suitable stabilizing annealing heat treatment have both excellent corrosion resistance and mechanical properties in the same time.
