本研究利用鑄造方法製備出Mg-10Y(wt.%)鑄錠合金，將其進行內部氫化製程，處理溫度為 300 °C ， 325 °C 及350 °C，吸氫壓力為0.34 MPa，分別以 10、24 及 36 小時之吸氫時間，1.5 小時放氫時間，探討內部氫化製程對於 Mg-10Y合金之影響，並對成分、相結構、機械性質進行分析。
研究結果顯示內部氫化350°C，24及36小時的試片完全氫化且原材中之Mg24Y5比Mg更容易被氫化，此條件下方塊狀之YH2均勻散佈在Mg基底中，然而退火作用及基底中釔濃度大幅減少，造成固溶強化效果降低，消除材料內應力，長時間熱處理也使晶粒成長，又因YH2物尺寸過大及散佈不均勻影響著散佈強化的效果，使硬度、降伏強度及抗拉強度皆大幅下降。
Mg24Y5在325°C，24小時可被完全分解成不規則狀且細小之YH2，基底中以不規則狀的團聚YH2及方塊狀YH2組成，此溫度下可維持原來之固溶原子濃度但晶粒成長使強化效果有限，硬度、降伏強度及抗拉強度仍然低於原材，延展性無明顯變化。Mg24Y5在低於325°C的溫度則無法被分解。
本研究最佳之內部氫化製程參數為325°C，24小時，此參數下Mg24Y5可被完全氫化，亦可維持原來之固溶原子濃度，但YH2的散佈強化效果被晶粒成長而抵銷，故與原材相比此參數之強度較低。

In this study, the Mg-10Y(wt.%) bulk alloy was prepared by casting process. The internal hydrogenation was carried out at 300, 325, and 350 ℃ under 0.34 MPa of hydrogen for 10, 24 and 48 hours, and followed by dehydrogenation for 1.5 hours. The effects of internal hydrogenation were investigated in Mg-10Y alloy. Also the behaviors of hydrogenation, microstructure, phase transitions and mechanical properties of Mg-10Y alloy were analyzed.
The results show that Mg24Y5 phase in Mg-10Y alloy is easier to be hydrogenated than Mg matrix, Mg24Y5 phases could be completely hydrogenated into cuboid YH2 phases after internal hydrogenation at 350 ℃ for 24 and 36 hours, and YH2 uniformly dispersed in Mg matrix. Because of the effect of annealing, releasing the interstrain of material. Moreover, the concentration of dissolved Y in the Mg matrix is greatly reduced by forming YH2, the effect of solid solution strengthening drastically reduce, also grain growth after longtime heat treatment. In addition, excessively large YH2 size makes the effect of dispersion strengthening unsatisfactory, making the hardness, yield strength and ultimate tensile strength are greatly reduced.
Mg24Y5 phase couldn’t be hydrogenated below 325°C. It could be completely hydrogenated into fine irregularity YH2 phase after internal hydrogenation at 325 ℃. The matrix is composed of irregular YH2 and cuboid YH2. The concentration of dissolved Y can be maintained at this temperature, but the strengthening effect is limited by the grain growth, and the hardness, yield strength and tensile strength are still lower than the as-cast Mg-10Y alloy. The best internal hydrogenation process parameter in this study is 325°C for 24 hours. Under this parameter, Mg24Y5 can be completely hydrogenated and the concentration of dissolved Y can be maintained, but the dispersion strengthening effect of the hydride is offset by grain growth. Therefore, the strength of this parameter is lower than that of as-cast alloy.

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