α′相形成与铁铬铝合金的脆性

a' Phase Formation and Embrittlement of Fe-Cr-Al Alloy

应用电子显微镜、X射线衍射技术,对低温长期使用的铁铬铝电热合金进行分析。结果表明:晶粒长大以及铬原子含量为75％左右的铁铬二元α＇相在晶界和基体中析出,是导致合金变脆的主要原因;通常微量碳化物Cr_(23)C_6相以及σ相总是沿晶界分布。

Using electron microscopy and X-ray diffraction techniques, the structure changes of Fe-Cr-Al alloy being used at low temperature for a long time were investigated. The results demonstrated that increase in embri-ttlement for the alloy was mainly caused by grain growth and a'-phase precipitation which contained 75 at% Cr; as usual, Small amount σ-phase and carbide Gr23C6 precipitated at grain boundaries.