本研究使用Mg97Y2Zn1(at.%)之鎂釔鋅合金作為基材進行熱氫處理，以200 ℃、250 ℃及300 ℃為處理溫度及4.83 MPa之吸氫壓力來進行熱氫處理，並分別以3、5及7小時之吸氫時間，1小時放氫時間來交叉分析，於成分、金相結構、機械強度方面來分析探討熱氫處理對於Mg97Y2Zn1合金之影響。
研究結果顯示，200 ℃之熱氫處理對於Mg97Y2Zn1合金對整體機械強度影響並不明顯，於250 ℃以上才會使材料表面原始之α-Mg及Mg12Y1Zn1相(長周期疊層相，Long Period Stacking Ordered Phase: LPSO)組成中的LPSO相轉變成Mg24Y5並且造成表面成分比例改變，其中300 ℃之試片更為明顯，也因為表面成分改變劇烈，較深層位置之成分也跟著變動造成內部LPSO相消失，且因溫度及處理時間增加而使得晶粒成長現象明顯，故強度沒有上升反而下降。而本研究最強拉伸強度於熱氫處理參數為250 ℃，5小時吸氫1小時放氫之熱氫處理試片中得到，其中原始之α-Mg及LPSO相轉變成Mg24Y5及表面成分比例改變，表面微觀結構細化且內部LPSO相並沒有受到影響而保持，且此強化之效果相較於晶粒成長之影響更為顯著，使得拉伸強度增強35 MPa(約30%)，降伏強度也增強38 MPa(約58%)。

In this study, was used as the substrate, the hydrogen treatment was carried out at 200 °C, 250 °C, 300 °C and 4.83 MPa for Mg97Y2Zn1 (at.%) alloy. The hydrogen absorption time was 3, 5, and 7 hours, and the. desorption time was 1 hour. The effects of thermal hydrogen treatment on composition, microstructure and mechanical properties of Mg97Y2Zn1 (at.%) alloy were studied.
The results show that the thermal hydrogen treatment at 200 °C has no effects on mechanical properties of Mg97Y2Zn1 (at.%) alloy. The transformation of Mg12Y1Zn1 phases (Long Period Stacking Ordered Phase: LPSO) to Mg24Y5 and the change of surface composition ratio were observed at 250 °C. The transformation is clearer at 300 °C. The internal LPSO phase disappeared due to change of composition. The grain growth was observed due to the increase of temperature and treatment time. The overall mechanical properties declined. The best thermal hydrogen treatment parameters in this study are 250 °C, 5-hour hydrogen absorption time and 1-hour hydrogen desorption time, the original LPSO phase transformed to Mg24Y5 and the surface composition ratio was changed, the surface microstructure is refined and the internal LPSO The phase is not affected and is maintained, and the effect of this strengthening is more significant than the grain growth, which increases the tensile strength by 35 MPa (about 30%) and the yield strength by 38 MPa (about 58%).

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