退火温度对SmCo永磁薄膜微结构及磁性能的影响

采用直流磁控溅射法制备SmCo薄膜，研究了退火温度对薄膜微结构及磁性能的影响。XRD分析结果表明，当退火温度为600℃时，SmCo5相析出，而Sm2Co17相在700℃析出。SEM照片可看出，退火温度高于900℃时，六方柱状的SmCo5相和菱方状的Sm2Co17相全部析出。随着退火温度的升高，晶粒尺寸增大，当温度达940℃时，晶粒尺寸减小，而在980℃时，晶粒尺寸又将增大。VSM测试表明，与制备态的薄膜相比，退火后的薄膜在垂直于膜面方向的矫顽力、剩余磁化强度及最大磁能积都增大。960℃时得到矫顽力和剩余磁化强度的最大值，800℃时得到最大磁能积的最大值。

Effects of annealing temperature on microstructures and magnetic properties of SmCo films

SmCo films were prepared by DC magnetron sputtering and annealed subsequently. The effects of annealing temperature on its microstructures and magnetic performances were investigated. XRD patterns show that the separation of SmCo5 phase and Sm2Co17 phase can be artificially controlled according to our requirement. SmCo5 phase is separated at 600℃ firstly and at 700℃ for Sm2Co17 phase separation. The film SEM images show that the hexagonal SmCo5 phase and rhombohedral Sm2Co17 phase are all separated out when annealing temperature is higher than 900℃. With the increase of annealing temperature, the size of the grain is increased. However,when temperature is increased up to 940℃ ,grain size is decreased,and increased again at 980℃. Compared to as-deposited films, annealed films perpendicular coercivities, remanences and maximum magnetic energy products measured by VSM are all increased. The maximum coercivity and remanence can be obtained at 960℃, and the maximum magnetic energy product can be obtained at 800℃.