XU Wenchong MA Xiang SUN Fuyu ZONG Guisheng Central Iron and Steel Research Institute
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Ministry of Metallurgical Industry
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Beijing
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China XU Wenchong
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Senior Engineer
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Department No.13
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Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
China
金属学报(英文版)
The strain-induced isothermal precipitation and the law of coarsening of Nb,V and Ti carbonitrides in Nb-steel.V-steel.Nb-V steel and Ti-V-Nb steel have been investigated systematically by means of STEM,EDAX,a new extraction replica technique and the quanti- tative phase analyses method.
关键词:
microalloyed steels
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null
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null
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null
WANG Yingshu SUN Fuyu XU Wenchong Central Iron and Steel Research Institute
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Ministry of Metallurgical Industry
,
Beijing
,
China Senior Engineer
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Department No.13
,
Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
China
金属学报(英文版)
By means of riM-190 hot-stage microscopy,the in situ observation of α-β transformation in 12Cr2MoWVTiB steel has been carried out.The sequence of the growth of ferritic needles composing bainitic basket has also been determined.According to the crystallographic analy- sis a multislip system transform model concerning the formation of basket has been proposed.
关键词:
α-β transformation
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null
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null
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null
Physica Status Solidi B-Basic Research
The electronic structure of the 13-atom Rh cluster is studied with the structure model optimized by Estiu and Zerner using the discrete variational local-spin density-functional method. The magnetic moment per atom of the cluster is calculated to be 0.54 mu(B), in good agreement with experimental measurements (0.48 +/- 0.13)mu(B). It confirms our previous assumption that the structural distortion of the Rh-13 cluster from a perfect icosahedron to its ground state geometry decreases its magnetic moment and makes the theoretical calculation close to the experimental measurement.
关键词:
molecules
Journal of Applied Physics
Alloys of PrCo13-xSix (1.5 less than or equal to x less than or equal to 4.0) have been prepared by are melting and subsequent annealing. X-ray powder diffraction proved that the alloys crystallized in the cubic NaZn13-type structure for x=1.5, and in the tetragonal NaZn13-derivative one for x greater than or equal to 2.0. Their Curie temperatures are almost independent of the Si content. Their magnetization curves exhibit a binary-step characteristic. The ac susceptibility curve indicates that there exists a magnetic transition below room temperature. The anomalous binary-step magnetization curves and the ac susceptibility curves versus temperature suggest a metamagnetic transition. (C) 1994 American Institute of Physics.
关键词:
王利刚
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特古斯
稀土
NaZn13型晶体结构的La(Fe,Si)13化合物由于具有原料价格低廉、磁热效应巨大、环保等优点而备受关注,已经成为国际上公认的最有潜力的室温磁制冷材料之一.本文系统介绍了La(Fe,Si)13化合物的结构和磁热性能,阐述了吸氢、吸氮,稀土元素、Co、B、C、Ca等替代元素对该系列化合物结构和磁热性能的影响,评述了最新的La(Fe,Si)13化合物的制备和加工工艺,最后展望了La(Fe,Si)13化合物作为磁制冷材料的发展趋势.
关键词:
磁制冷
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磁热效应
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La(Fe,Si)13化合物
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磁熵变
叶四友
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刘建永
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杨伟
表面技术
doi:10.16490/j.cnki.issn.1001-3660.2015.08.015
目的：研究获得高质量H13激光涂层的工艺。方法以H13合金粉末为熔覆材料,在H13钢退火基体表面制备H13合金涂层,采用均匀设计试验,利用金相法检测涂层的几何形貌参数,得到涂层宽度回归模型,并验证所建立模型的准确性。利用光学显微镜和扫描电镜分析涂层的显微组织形貌,对涂层成分进行分析,通过显微硬度计测试涂层截面的显微硬度分布。对涂层气孔、裂纹和成分偏析进行分析。结果扫描速度22 mm/s ,激光功率1300 W,送粉速率21 g/min时,H13合金涂层与基体呈良好的冶金结合,涂层内组织均匀致密,无裂纹缺陷,截面显微硬度约600~699HV,是H13基体硬度的2.4~3倍。扫描速度14 mm/s ,激光功率1400 W,送粉速率42 g/min 时,涂层的截面显微硬度约为669~698HV,是基体的2.85~3倍。结论在两种工艺条件下,均能获得质量较优的H13合金涂层。
关键词:
激光熔覆
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H13合金涂层
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几何形貌
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均匀设计
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回归模型
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显微硬度
Physica Status Solidi a-Applied Research
The crystal structure and magnetic properties of LaCo13-xAlx compounds have been investigated by X-ray powder diffraction and magnetization measurement. X-ray powder diffraction shows that the compounds crystallize in cubic NaZn13-type structure with lattice parameter a=11.345(2) to 11.473(4) Angstrom in the range of x less than or equal to 2.7, and in the tetragonal Ce2Ni17Si9 structure at x=3. Magnetization measurements reveal that both cubic and tetragonal LaCo13-xAlx are ferromagnetic with Curie temperature higher than 840 K, and the magnetic moment per Co atom in LaCo13-xAlx compounds decreases with Al content.
关键词:
intermetallic compounds;rare-earth;transition
