熔体冷速对Co_(48)Cr_(15)Mo_(14)C_(15)B_6Er_2块体非晶合金晶化及磁性能的影响  

Effect of Melt Cooling Rate on Crystallization and Magnetic Properties of Co_(48)Cr_(15)Mo_(14)C_(15)B_6Er_2 Bulk Metallic Glass

作　　者：袁子洲[1] 姚林[1] 包石磊[1] 王英君[1] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,甘肃兰州730050

出　　处：《稀有金属材料与工程》2009年第6期999-1004,共6页Rare Metal Materials and Engineering

基　　金：甘肃省教育厅开放基金(0503-08);兰州理工大学优秀中青年基金(Q200303)项目资助

摘　　要：分别用单辊甩带法和铜模铸造法制备了Co48Cr15Mo14C15B6Er2非晶合金薄带以及Φ2mm和Φ7mm的非晶圆棒。利用差热分析仪和振动样品磁强计研究了冷却速率对Co48Cr15Mo14C15B6Er2非晶合金的晶化动力学及磁性能的影响。结果发现,冷却速率对晶化动力学有显著影响。对非等温晶化来说,随着冷速降低,试样的玻璃转变温度下降,玻璃转变激活能减小。虽然晶化峰值温度不受冷速的影响,但是晶化激活能随冷速降低而降低。对等温晶化来说,虽然不同冷速条件下制备的试样都表现出扩散控制的晶核三维长大过程,但是形核速率随时间增加而降低的速度与冷速有关。冷速越快,降低速度越快,同时晶化孕育时间越短。Co48Cr15Mo14C15B6Er2非晶合金的磁性能受冷却速率的影响很大。冷速高时,合金表现为顺磁性;冷速低时,合金表现为铁磁性。饱和磁感应强度随冷速的降低而增大。The Co48Cr15Mo14C15B6Er2 amorphous ribbon and rods with diameters of 2mm and 7mm were prepared by melt spinning and copper mold casting. The different Scanning calorimetry and the vibrating sample magnetometer were employed to investigate the effect of cooling rate on crystallization kinetics and magnetic properties of metallic Co48Cr15Mo14C15B6Er2 glass. It was found that the cooling rate had significant influence on the crystallization kinetics. In the case of non-isothermal crystallization process, the glass transition temperature and the activation energy for the glass transition decreased with decreasing of cooling rate. The activation energy for crystallization also decreased with decreasing of cooling rate, in despite of that the peak temperature of crystallization was independent of cooling rate. Although the isothermal crystallization was governed by diffusion-controlled three-dimensional growth with decreasing of nucleation rate for Co48Cr15Mo14C15B6Er2 glasses under different cooling rates, how rapidly the nucleation rate decreased was related to cooling rate. The more rapid the cooling rate was, the faster the decrease of the rate was. The magnetic properties of Co48Cr15Mo14C15B6Er2 glass was significantly affected by cooling rate. The sample obtained at high cooling rate took on paramagnetic property, whereas the sample obtained at low cooling rate took on ferromagnetic property. The saturation magnetization increased with decreasing of cooling rate.

关 键 词：钴基非晶合金 冷却速率 晶化动力学 磁性能 

分 类 号：TG139.8[一般工业技术—材料科学与工程]