Effect of Test Methods on the Accuracy of High-Temperature Oxidation Kinetics of Al-2Li Alloy

Due to the high activity of Li, it is easy to react with the crucible during the melting process, which makes it difficult to measure the oxidation kinetics of aluminum-lithium alloy accurately. In order to achieve high precision in the experiment, the oxidation behavior of graphite crucibles and corundum crucibles at high temperatures was separately studied. And the high-temperature oxidation kinetics of Al-2Li alloy in isostatic pressed high-purity graphite crucible and corundum crucible were compared. The results show that although the weight loss of graphite crucible is improved after BN coating, it is still difficult to accurately measure the oxidation kinetics of the alloy. But the quality of the corundum crucible coated with BN remains stable at high temperatures. The results also show that the weight gain of the alloy in the suspended state in the crucible is less than that in the horizontal state. Therefore, it is more suitable to use the corundum crucible coated with BN in the high-temperature oxidation experiment of aluminum-lithium alloy, and the sample should be placed in the air during the test process to achieve the purpose of uniform thermal oxidation.