鋁－鎂熔融合金高溫氧化機構之研究

A Study on the High Temperature Oxidation of Molten Aluminum-Magnesium Alloys

石富順(Fuh-Shuenn Shyr)

《鑛冶：中國鑛冶工程學會會刊》 41卷4期 (1997/12) Pp. 72-76

https://doi.org/10.30069/MM.199712_41(4).0006

摘要

鋁－鎂合金在高溫熔煉時容易產生氧化現象，形成大量的金屬損失及產生介在物之危害。本研究以熱重分析儀探討高鎂鋁合金在高溫熔融態時之氧化現象，其氧化損失量受鎂含量高低、處理溫度及時間之影響，同時氧化過程先經歷緩慢氧化期，再進入快速氧化階段。當氧化物形成結晶態的MgO或MgAl_2O_4時，其氧化速率即急速上升。實驗結果顥示高鎂鋁合金在熔湯處理溫度高於750℃時，靜置時間應在2小時以內，以避免進入快速氧化階段。

關鍵字

鋁－鎂熔融合金 ； 高溫氧化 ； 熱重分析儀 ； 金屬損失

並列摘要

The oxidation of molten aluminum containing magnesium induces tremendous metal losses and inclusion formation during industrial melting operations. In this paper, the high temperature oxidation of molten Al-Mg alloys has been studied with a thermogravimetric device. The results show that the degree of oxidation increases with increasing the magnesium content, treating temperature and time. The oxidation rate is smooth at the initial stage but accelerates rapidly when the oxide transforms to crystalline MgO and MgAI_2O_4 from amorphous form after an incubation period. In order to prevent the tremendous metal losses, it is suggested that the operational interval has to be reduced to less than 2 hours when the temperature of molten Al-Mg alloy exceeds 750℃.

並列關鍵字

Molten Al-Mg alloys ； High temperature oxidation ； Thermogravimetry ； Metal losses