M5200合金係一高Mg含量的鍛造鋁合金，由520.0鑄造鋁合金(Al-10Mg)改良而成。本研究欲探討安定化熱處理是否具有改善材料性質之功能，並藉由非破壞性檢測技術(導電度量測)，探討敏化試驗對M5200(Al-10Mg)鍛造合金機械性質與腐蝕抗性的影響。實驗結果顯示，M5200(Al-10Mg) 鍛造合金於285 ℃下進行1h的安定化熱處理，結構為回復(recovery)及極輕微的再結晶(recrystallization)，使得材料不至於因為敏化，大量β相析出導致抗腐蝕能力的降低。而重量損失測試(依規範ASTM-G67)顯示，合金雖具有中度沿晶腐蝕敏感性之隱憂，但因M5200屬於鎂含量極高之合金，此G67試驗之結果仍在可以接受之範圍內，也證實可以利用且非破壞性檢測技術(導電度)來預測合金之硬度、與G67 重量損失，且其預估值之誤差率皆在10 %以內。;M5200 is a forging alloy that contains high magnesium content, which is modified from 520.0(Al-10Mg) casting alloy. In this study, we intended to investigate whether stabilizing treatment is capable to improve the material’s properties or not. We also utilized non-destructive testing technology (electrical conductivity), to discuss the influence of sensitization on M5200 alloy’s mechanical properties and corrosion resistance. The results suggested that under 285 ℃/1h stabilizing treatment, the microstructure of M5200 showed a recovery texture and minor recrystallization; hence, even the abundant β phase precipitate, the material’s corrosion resistance will not decay significantly. Although the ASTM G67 Standard Test indicated that M5200 has relatively severe intergranular corrosion, but for such alloy which contains high percentage of magnesium, the result of ASTM G67 Standard Test is still acceptable. Furthermore, non-destructive testing technology also prove the conductivity, hardness and G67 Standard Test have a certain extent of correlation ship. Through the linear regulation, the deviations between the Trend line and real data are smaller than 10 %.
