本研究主要探討時效處理溫度及預壓縮變形參數對鎂-鋁系合金材料性質的影響，實驗中採用A61、AZ80以及AZ91三種材料，於固溶處理後各施加0%、0.2%及2%的預壓縮變形參數，接著對各試片進行140℃及212℃的時效處理，藉由材料平均硬度及耐蝕性變化，分析探討合金成份、析出物形態及析出物密度對材料硬度及耐蝕性的影響。 鎂-鋁合金只有一種穩定析出相Mg17Al12，但該析出相卻具有連續型與非連續型兩種不同的形態，且各具不同的性質。實驗結果發現，AZ61由於析出物量甚少，因而不同溫度與變形條件對其時效處理後的材料性質影響不大。212℃時效處理後，AZ80與AZ91則由於晶粒大小差異，造成析出形態的不同，其中AZ91多數形成連續型析出物，而AZ80則多數形成非連續型析出物。藉由預壓縮變形處理，可使AZ80內形成較多量的連續型析出物，亦可幫助AZ91內的析出物密度增高，而提升材料形質。 140℃時效處理後，AZ80與未經預壓縮變形的AZ91試片硬度略微提升，而腐蝕損耗率則與時效時間成正比；預壓縮變形後的AZ91經140℃時效處理後，硬度會提升甚多，而其腐蝕損耗率則會與時效時間成反比。 The experimental materials are AZ61, AZ80 and AZ91. After solution treatment, the specimens are strained with 0%, 0.2% and 2% compression, then the specimens are aged at 140℃ and 212℃. The hardness and the corrosion resistance of magnesium alloys are affected by the mode, the quantity of precipitates and the alloy components. There are two modes of Mg17Al12 precipitate, continuous and discontinuous. Each mode has different properties. The experimental results show that: 1. After aging treatment at 212℃, the precipitates in AZ91 are mainly continuous mode, but in AZ80 are mainly discontinuous precipitates. 2. Compared with the specimens after aging treatment at 212℃, the hardness and corrosion resistance of AZ80 and AZ91 would raise with pre-strain treatment. 3. After aging treatment at 140℃, the corrosion resistance of all AZ80 and non-strained AZ91 specimens would decrease with increasing the aging time, but the hardness are almost the same. 4. After aging treatment at 140℃ for a long time, the hardness and the corrosion resistance of AZ91 could increase largely with pre-strain treatment.
