添加Cr3C2对SmCo7合金的组织结构及磁性能的影响  

Influence of Cr_3C_2 addition on microstructure and magnetic properties of SmCo_7 alloy

作　　者：张广腾[1] 易健宏[1] 李丽娅[1,2] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083 [2]中国科学院宁波材料技术与工程研究所,宁波315201

出　　处：《粉末冶金材料科学与工程》2009年第2期123-126,共4页Materials Science and Engineering of Powder Metallurgy

基　　金：湖南省自然科学基金资助项目(04JJ6029)

摘　　要：采用熔体快淬法制备(SmCo7)100-x(Cr3C2)x(x为摩尔分数,%。x=0～7)合金薄带。通过X射线衍射(XRD)、热磁分析(TMA)、振动样品磁强计(VSM)、扫描电镜(SEM)和透射电镜(TEM)研究Cr3C2添加量x对合金相结构、微观组织和磁性能的影响。结果表明,当Cr3C2含量x由0增加到7时,(SmCo7)100-x(Cr3C2)x的矫顽力由33.2 kA/m显著增加到595.7 kA/m,同时主相的晶粒尺寸显著降低,合金形成了1:7 H的主相结构。第二相的结构随Cr3C2含量增加而变化,由2:17 H相逐渐转变为2:17 R相和2:7相。在高Cr3C2含量的合金(x=7)中析出了含有Cr、Co、C的晶间非磁性相,该相通过抑制主相晶粒尺寸的长大及对畴壁的钉轧来提高合金的矫顽力。Melt-spun ribbons （SmCo7）100-x（Cr3C2）x（x=0-7） have been obtained at a wheel-surface speed of 20 m/s. The influences of the Cr3C2 content on structural and magnetic properties of the alloy ribbon have been systematically investigated using X-ray diffractometer（XRD）, thermomagnetic apparatus（TMA）, vibrating sample magnetometer（VSM）, scanning electron microscope（SEM） and transmission electron microscope（TEM）. With the Cr3C2 content x increasing from 0 to 7 at%, iHc increases from 33.2 kA/m to 595.7 kA/m. （SmCo7）100-x（Cr3C2）x are formed in a hexagonal structure with a major phase of 1：7 H. A small amount of secondary phase is also detected in the alloys. As the Cr3C2 content increases, 2：17 H phase as a secondary phase transforms to 2：17 R and 2：7 phases. A non-magnetic phase is also found in the alloys with x=7at% along the grain boundaries, which mainly consists of Cr, Co and C and can refine the microstructure and perform as magnetic domain pinning sites, resulting in improved iHc.

关 键 词：快淬 SmCo7 碳化铬(Cr3C2) 微结构 磁性能 

分 类 号：TF125.8[冶金工程—粉末冶金]