篇名 | 鋁化改質效應對MoSi2基合金抗高溫氧化之研究 |
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卷期 | 28:3 |
並列篇名 | Effects of Aluminizing Treatments on Hightemperature Oxidation of MoSi2-based Alloys |
作者 | 周鈺峰 、 何昱瑾 、 開物 |
頁次 | 105-110 |
關鍵字 | 鋁化改質 、 MoSi2 合金 、 高溫氧化 、 氧化動力學 、 反應機制。 、 Aluminizing Treatments 、 MoSi2 、 alloys 、 High-temperature oxidation 、 Oxidation kinetics 、 Reaction mechanism 、 EI |
出刊日期 | 201409 |
本研究探討Mo-Si 基三元合金經熔煉(MoSi2)90Al10 (MSA10)及其在經固體滲鋁改質之試 片(MS-A),於700 ~ 1100 °C 之空氣下的氧化行為。研究結果顯示,MSA10 合金在700 ~ 800 °C 呈現加速氧化現象,但在900 °C 以上具有良好的抗氧化性質;另一方面,MS-A 合金在 800 °C 之氧化動力學是加速反應,而900 °C 則遵守拋物線律,且氧化速率隨溫度增加而趨 緩,但在1000 °C 以上則呈現嚴重的氧化失重現象。由顯微結構分析得知,MSA10 在800 °C 氧化所形成的Al2O3 氧化層較為鬆散,保護性較差;在900 °C 以上氧化後,其表面會形成 較緻密的α-Al2O3 保護層,能有效地提升MoSi2 的抗氧化能力;而MS-A,經氧化後亦會生 成具保護層的α-Al2O3,但會有較多且不連續裂縫,其保護效果較差。
The effects of adding 10 at.% Al to form (MoSi2)90Al10 and surface aluminizing (MS-A) on the isothermal oxidation of MoSi2-based alloys were investigated over the temperature range of 700 ~ 1100 °C in dry air. The breakaway kinetics of the MSA10 alloy was observed at T ≤ 800 °C, however, the parabolic kinetics with better oxidation resistance was noted at T ≥ 900 °C. On the other hand, the mass-loss kinetics was observed at T ≥ 1000 °C for the MS-A alloy. The Al2O3 layer formed on the MSA10 at 800 °C that provided poor oxidation resistance. However, the scales formed on MSA10 was composed of α-Al2O3 at T ≥ 900 °C, whose formation is responsible for the better oxidation resistance. On contrast, the α-Al2O3 layer formed on the MS-A alloy containing numerous crackes, which provided poor oxidation resistance.