Co基非晶丝退火处理及巨磁阻抗效应  

Annealing Treatment and Giant Magneto Impedance of Co-Based Amorphous Wires

作　　者：张树玲[1] 邢大伟[1] 王欢[1] 孙剑飞[1] 

机构地区：[1]哈尔滨工业大学材料科学与工程学院

出　　处：《钢铁研究学报》2010年第7期38-41,共4页Journal of Iron and Steel Research

摘　　要：采用熔体抽拉法制备了直径59μm的Co68.25Fe4.5Si12.25B15非晶丝,在400、500℃进行了不同工艺的退火处理,分析了退火处理对Co基丝磁阻抗(GMI)效应的影响。结果表明,400℃退火处理降低了丝的各向异性场,提高GMI效应和双峰出现频率,并大幅提高了磁场响应灵敏度。400℃保温20 min退火样品双峰出现频率提高至13 MHz。400℃保温80 min退火样品低频GMI效应最强,最大阻抗变化率ΔZ/Z达到468.6%,5 MHz时磁场响应灵敏度为0.73%(m/A)。500℃退火,由于晶化相析出导致软磁性能和GMI效应的降低,双峰出现频率降至3 MHz。试验表明退火处理可以有效提高材料的灵敏度,获得适合磁传感器应用的磁敏丝材。Co68.25Fe4.5Si12.25B15 amorphous wires with diameter of 59 μm were prepared and subjected to conventional annealing at 400 ℃ and 500 ℃ through melt extraction method.The giant magneto impedance（GMI） effect of the as-cast and annealed wires was analyzed at low frequencies（0.1 MHz-13 MHz）.The results show that GMI response and field sensitivity are improved after suitable annealing treatment.The anisotropy field is decreased after anneal treatment at 400 ℃,and the double-peak GMI appearance is induced at a higher frequency.The double-peak GMI appearance is increased to 13 MHZ for the wires annealed at 400 ℃ holding for 20 min.Best GMI effect is obtained by annealing at 400 ℃ and holding for 80 min.The largest impedance ratio ΔZ/Z is as high as 468.6% and the field sensitivity goes up to 0.73%（m/A） at 5 MHz.When annealing temperature rises to 500 ℃,both the magnetic softness and GMI response are reduced due to crystallization with double-peak GMI appearance at 3 MHz.The annealing method is effective for obtaining high quality wires suitable for novel field GMI sensors applications.

关 键 词：退火 GMI效应 非晶丝 各向异性场 

分 类 号：TG156.2[金属学及工艺—热处理]