高矫顽力型FeCrCo合金相变化的穆斯堡尔谱研究

Mssbauer spectra study on phase variation in a high-coercivity FeCrCo alloy

通过穆斯堡尔谱、透射电镜、x射线和磁测量等手段研究了将普通FeCrCo合金中Cr,Co元素含量提高、并加入Mo,Zr元素后合金矫顽力的变化,发现其值76kAm比普通值40—52kAm高50%以上.对该合金不同热处理阶段的穆斯堡尔谱的测试表明,合金的微观结构与普通FeCrCo合金有显著的不同.固溶处理后合金单相性好,不产生对磁性起破坏作用的γ相;磁场热处理过程中,发生原子的重新排布,α2相开始出现,两相结构基本确定;分级回火后,调幅分解进行得更彻底,合金内部完全形成调幅结构,与低矫顽力合金相比,铁磁性的α1相更容易形成.

Variation of the coercivity induced by increasing Cr and Co contents and adding inpurities ot Mo and Zr in FeCrCo alloys was investigated using Moessbauer spectra, fransmission electron microscopy, x-ray diffraction, and magnetic measurement. A coercivity as high as 76kA/m is obtained, which is one and half times higher than that （40-52kA/m） of the common alloy. Moessbauer spectra shows that the microstructure of the high-coercivity alloy is apparently different from that of the traditional FeCrCo alloy. The alloy is single-phase after solution treatment, the non-magnetic γ phase, which weakens the magnetic properties, does not appear. During the thermomagnetic treatment, the atomic distribution is rearranged, and leads to the formation of the α2 phase, the spinodal structure with the two-phase （α1 ＋ α2） in the alloy fully forms after step-tempering. It might be beneficial for forming the high coercivity in alloy. Comparied with the low-coereivity case, more of the α1 phase exist in the spinodal structure.