论文部分内容阅读
首次制备出具有高稳定性的Sm Co_(8.9)Si_(0.9)纳米晶合金,进而系统研究了亚稳相Sm Co_(8.9)Si_(0.9)的相变特征及相应的磁性能变化规律。发现添加元素Si可以有效提高过饱和固溶体亚稳相SmCo_(9.8)的稳定性,随着热处理温度的升高,SmCo_(8.9)Si_(0.9)纳米晶合金由SmCo_(9.8)(H)结构的单相转变为Sm_2Co_(17)(H)和Co(fcc)相,且伴随相变,矫顽力提高。其机理源于析出的细小Co相造成钉扎机制增强。进一步升高热处理温度,Sm_2Co_(17)(H)相转变为Sm_2Co_(17)(R)相,同时晶粒长大明显且晶粒尺寸分布不均匀,导致磁性能下降。
The SmCo_ (8.9) Si_ (0.9) nanocrystalline alloy with high stability was prepared for the first time. The phase transition characteristics and corresponding magnetic properties of SmCo_ (8.9) Si_ (0.9) were systematically investigated. It is found that the addition of Si can effectively improve the stability of SmCo_ (9.8) in the supersaturated solid solution. With the increase of the heat treatment temperature, the SmCo_ (8.9) Si_ (0.9) Single phase transformation into Sm_2Co_ (17) (H) and Co (fcc) phase, and with the phase change, coercivity increased. The mechanism stems from the precipitation of small Co-induced pinning mechanism increased. Further increasing the heat treatment temperature, Sm_2Co_ (17) (H) phase was changed to Sm_2Co_ (17) (R) phase. Meanwhile, the grain growth was obvious and the grain size distribution was not uniform, which led to the decrease of magnetic properties.