Summary: | 碩士 === 國立中央大學 === 機械工程學系在職專班 === 107 === This research discusses potential methods of improving the properties of casting alloy B535.0 (Al-7Mg) and further explored the optimal conditions for stabilizing treatment for a new alloy named MB5350 (Al-7Mg). Though non-destructive analytical testing techniques such as conductivity test, we further studied the corrosion and mechanical properties of MB5350 (Al-7Mg) alloy in response to sensitization reaction. The result of research indicated that the forging alloy of MB5350 (Al-7Mg) can get the better stability condition under the annealing process for 280 ℃, 1H. Recovery and partial recrystallized structure was found by microstructure under this condition. Furthermore, the sensitization time can cause β-phase (Mg2Al3) precipitation amount increased, and the trend of electrical conductivity show consistent as well. Yet, after ASTM G67 standard test still showed slight potential intergranular corrosion. As a result, we conclude that 280 ℃,1h is the optimal stabilization condition for MB5350 (Al-7Mg). Besides, the influence of the sensitization process for the mechanical property (Corrosion Resistance and Hardness) of MB5350 (Al-7Mg) can be effectively evaluated by the Non-Destructive Testing (Conductivity Measurement) which deviation can control within 12 %.
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