Thermal and magnetic properties of bulk Fe-based glassy alloys prepared by copper mold casting
Thermal and magnetic properties of bulk Fe-based glassy alloys prepared by copper mold casting
复制标题
DOI：
10.2320/matertrans1989.36.1427
复制
发表时间：
1995-12-01
期刊：
影响因子：
--
通讯作者：
Gook, JS
中科院分区：
文献类型：
--
作者：
Inoue, A;Shinohara, Y;Gook, JS
采用铜模铸造方法制备了直径分别为0.5和1.0 mm的圆柱形Fe73Al5Ga2P11C5B4合金。直径的进一步增大导致1.5 mm（φ）试样形成Fe-3（B， C）、Fe2B和Fe3P共存的玻璃相，2.0 mm（φ）试样形成Fe-3（B， C）、Fe2B和Fe3P共存的玻璃相。值得注意的是，玻璃形成的最大厚度大约是目前报道的铁基玻璃合金最大厚度的10倍。1.0 mm（φ）玻璃化合金的玻璃化转变温度（T-g）、结晶温度（T-x）和结晶热分别为732 K、785 K和3.76 kJ/mol。大块玻璃合金和熔融纺丝带在热稳定性和磁性能方面没有明显的差异。该1.0 mm（φ）玻璃合金具有铁磁性，居里温度为606 K，室温下饱和磁化强度（B-s）为1.26 T，矫顽力（H-c）为82 a /m，剩余磁化强度与B-s之比为0.38。同时含有5种溶质元素的铁基合金具有较大的δ T-x（=T-x- t -g）和较大的非晶形成能力。乘法的有效性大概是由于以下三种效应的结合；(1)对于含有P、C、B等不同原子大小的玻璃结构，由于增加了密集的随机堆积密度而抑制了晶核；(2)由于产生了具有强吸引键性质的类al金属对，导致类fe金属化合物的原子重排难以析出；(3)与B、C不相溶、与Fe可溶的Ga的溶解降低了Fe-B和Fe-C化合物的优先沉淀倾向。
Bulk glassy Fe73Al5Ga2P11C5B4 alloys in cylindrical form with diameters of 0.5 and 1.0 mm were found to form by a copper mold casting method. The further increase in diameter causes the formation of coexistent glassy, Fe-3(B, C), Fe2B and Fe3P phases for the 1.5 mm(phi) sample and coexistent Fe-3(B, C), Fe2B and Fe3P phases for the 2.0 mm(phi) sample. It is to be noticed that the maximum thickness for glass formation is about 10 times larger than the largest thickness for Fe-based glassy alloys reported up to date. The glass transition temperature (T-g), crystallization temperature (T-x) and heat of crystallization of the 1.0 mm(phi) glassy alloy are 732 K, 785 K and 3.76 kJ/mol, respectively. No appreciable difference in the thermal stability and magnetic properties is seen between the bulk glassy alloys and the melt-spun ribbon. The 1.0 mm(phi) glassy alloy has ferromagnetism with a Curie temperature of 606 K and exhibits 1.26 T for saturation magnetization (B-s), 82 A/m for coercivity (H-c) and 0.38 for the ratio of residual magnetization to B-s at room temperature. The large Delta T-x(=T-x-T-g) and large glass-forming ability can be obtained for the Fe-based alloy containing simultaneously the five solute elements. The effectiveness of the multiplication is presumably due to the combination of the following three effects; (1) the suppression of crystalline nuclei due to the increase in dense random packing density for the glassy structure containing P, C and B with significantly different atomic sizes, (2) the difficulty of atomic rearrangements for the precipitation of the Fe-metalloid compounds caused by the generation of Al-metalloid pairs with strongly attractive bonding nature, and (3) the decrease in the preferential precipitation tendency of Fe-B and Fe-C compounds by the dissolution of Ga which is immiscible to B and C and soluble to Fe.