涂国超
,
张家骥
,
季雨
,
史长利
金属学报
本文研究了nm级微晶软磁材料Fe-Cu-Mo-Si-B合金系在不同磁退火方式以及不同热处理温度下磁性能的变化。结果表明,最佳热处理为510℃,保温1h;以缓慢冷却性能最好,并利用透射电镜,X射线衍射及热磁曲线对最佳热处理状态下的样品进行了组织观察和结构确定。该材料由两相组成:一相是a-FeSi固溶体,尺寸在10—20nm之间;另一相为非晶态。
关键词:
纳米微晶
,
soft magnetic material
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Fe-base alloy
L.J.Shang
金属学报(英文版)
A gradient coating of Fe-based alloy was manufactured with rare earths (RE) by plasma surfacing on Q235 steel substrate. The coatings were studied by using X-ray diffraction (XRD), scanning electron microscope (SEM), differential thermal analyzer (DTA), and electron probe micro-analyzer (EPMA). The results show that the phases of the two kinds of coatings(with and without RE) both include α-Fe, Fe7C3， Fe3C, Cr2B, Fe2B and FeB. The microstructure of F314 coating is mainly hypereutectic, the pro-phases Cr7C3 and Cr2B are loose, crassi, spiculate and contain microcracks. The brittleness of the coating is high, and the average hardness is 787 HV. When 0.8wtRE was added into the F314 alloy, the microstructure varied from hypoeutectic to hypereutectic continuously, The hardness appears as gradient distribution with the highest value of 773 HV, meanwhile, the brittleness decreases significantly. The formation of gradient structure depends on the fallowing factors: (i) the conversion of RE. The addition of RE lowers the elements point and Fe-C eutectic temperature, thus the base metal melting acutely. (ii) the heating of plasma arc.Graded temperature results in directional solidification, thus the gradient structure forms easily. The main reasons for the hardness decrease with RE addition in the alloy are the ratio of hard phase lowering and the hardness of the hard phase decreasing.
关键词:
rate earth
,
null
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