两类Ni-Fe基合金抗氧化性能的对比研究

用热压法制备了2种成分的Ni-Fe-X基合金, 并在1 000 ℃和1 200 ℃进行了大气氧化试验。XRD、SEM、EDX和金相分析表明, Ni-11Fe-10Cu-6Al-3Zn的氧化层致密, 主要由Ni、Fe和Al混合氧化物组成, 合金中Cu显示较强的抗氧化性能, 是由于铝的优先氧化的结果, 氧化膜中较多的尖晶石的存在有效改善了氧化物结构, 提高了合金的抗氧化性能。Fe-Ni合金氧化膜主要是铁氧化物, 由于氧化膜抗热震性差使得氧化膜与基体中存在较多的裂纹, 导致合金氧化膜疏松, 是该合金抗氧化性能差的主要原因。

Comparison of Oxidation-resistance Property Between Two Kinds of Ni-Fe Alloys

Two kinds of Ni-Fe-X alloys were prepared by hot pressing and oxidation-resistance tests were carried out under 1 000 ℃ and 1 200 ℃. Through XRD, SEM, EDX and metallographic analysis, it was concluded that oxidation film of Ni-11Fe-10Cu-6Al-3Zn was dense. The film was mainly made up of oxide mixture of Ni, Fe and Al. The reason that copper in the alloy showed good oxidation-resistance was due to the preferential oxidation of aluminum. The microstructure of oxide and oxidation-resistance of alloy was improved by spinal in the film. The oxide film of Fe-Ni alloy was mainly made up of iron oxide. Its poor shock-resistance led to much crack in the matrix and oxide film, which resulted in porous oxide film, and lower oxidation resistance of the alloy.