Enhancement of glass-forming ability and thermal stability of a soft magnetic Co(75)B(25)metallic glass by micro-alloying Y and Nb
Enhancement of glass-forming ability and thermal stability of a soft magnetic Co(75)B(25)metallic glass by micro-alloying Y and Nb
复制标题
Y和Nb微合金化增强软磁Co(75)B(25)金属玻璃的玻璃形成能力和热稳定性
DOI：
10.1007/s42243-020-00489-8
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发表时间：
2021
影响因子：
2.5
通讯作者：
Wei Zhang
中科院分区：
文献类型：
--
作者：
Feng Bao;Yanhui Li;Zhengwang Zhu;Xinyu Liang;Yan Zhang;Wei Zhang
通过将 Y 和 Nb 微合金化成 Co75B25 合金，开发了不含 Fe 的软磁 Co 基 Co-Y-Nb-B 大块金属玻璃 (BMG)。首先，添加 3–4 at.% Y 会促进玻璃化转变的发生，并增加过冷液体稳定性和磁软度。 Co71.5Y3.5B25 金属玻璃具有 33 K 的大过冷液体区域 (ΔTx) 和 1.5 A/m 的低矫顽力 (Hc)。随后将 2–4 at.% Nb 合金化到 Co71.5Y3.5B25 合金中，进一步将 ΔTx 扩大到 50 K，将 Hc 降低到 0.9 A/m，并能够形成临界样品直径高达 2.0 mm 的 BMG。合金化的Nb导致结晶过程中形成复杂的(Co,Nb,Y)23B6竞争相，并在凝固过程中扩大熔体过冷度，从而分别提高过冷液体稳定性和玻璃形成能力。 Co-Y-Nb-B BMG 还表现出良好的软磁和机械性能，即低 Hcof 0.9-1.2 A/m、相对较高的饱和磁通密度 0.36-0.57 T、高屈服强度 3877-3930 MPa、塑性应变 0.2%-0.3% 以及高维氏硬度 1156-1201。所开发的软磁钴基 BMG 在结构和功能材料方面具有广阔的应用前景。
Soft magnetic Co-based Co–Y–Nb–B bulk metallic glasses (BMGs) without Fe have been developed by micro-alloying Y and Nb into a Co75B25alloy. First, addition of 3–4 at.% Y promotes the occurrence of glass transition and increases the supercooled liquid stability and magnetic softness. Co71.5Y3.5B25metallic glass possesses a large supercooled liquid region (ΔTx) of 33 K and low coercivity (Hc) of 1.5 A/m. Subsequent alloying 2–4 at.% Nb into Co71.5Y3.5B25alloy further enlarges ΔTxto 50 K, lowersHcto 0.9 A/m, and enables the formation of BMGs with a critical sample diameter up to 2.0 mm. The alloying Nb causes the formation of complex (Co, Nb, Y)23B6competing phase during crystallization and widens the melt undercooling during solidification, which improves the supercooled liquid stability and glass-forming ability, respectively. Co–Y–Nb–B BMGs also exhibit good soft magnetic and mechanical properties, i.e., lowHcof 0.9–1.2 A/m, relatively high saturation magnetic flux density of 0.36–0.57 T, high yielding strength of 3877–3930 MPa with plastic strain of 0.2%–0.3%, and high Vickers hardness of 1156–1201. The developed soft magnetic Co-based BMGs are promising for applications as structural and functional materials.