Nanocrystalline Fe–C alloys produced by ball milling of iron and graphite
Nanocrystalline Fe–C alloys produced by ball milling of iron and graphite
复制标题
通过球磨铁和石墨生产纳米晶 Fe-C 合金
DOI：
10.1016/j.actamat.2013.02.006
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发表时间：
2013-05
期刊：
影响因子：
9.4
通讯作者：
Kirchheim, R.
中科院分区：
文献类型：
--
作者：
Chen, Y. Z.;Herz, A.;Li, Y. J.;Borchers, C.;Choi, P.;Raabe, D.;Kirchheim, R.
制备了一系列不同碳含量（xtot.%）的纳米晶Fe-C合金，（4.90wt.%）通过球磨制备。这些合金的微观结构通过透射电子显微镜和X射线衍射进行表征，碳在晶界和晶粒内部之间的分配通过原子探针断层扫描确定。结果表明，碳向α铁素体晶界的偏聚可使其晶粒尺寸显著减小到几个纳米。当铁素体的晶界被碳饱和时，基体和晶界之间接近亚稳态热力学平衡，导致晶粒尺寸随着xtot的增加而减小。当xtot>6.19at.%时，合金的尺寸最终达到6 nm左右的下限（1.40wt.%）; xtot的进一步增加导致碳以Fe 3C的形式沉淀。在19.4at.%时观察到非晶结构的存在。C（4.90重量%）合金的非晶化归因于通过剧烈塑性变形导致的变形驱动的Fe 3C非晶化。通过对一种含1.77at.%为纳米晶合金中达到的亚稳平衡提供了额外的证据。
A series of nanocrystalline Fe–C alloys with different carbon concentrations (xtot) up to 19.4at.% (4.90wt.%) are prepared by ball milling. The microstructures of these alloys are characterized by transmission electron microscopy and X-ray diffraction, and partitioning of carbon between grain boundaries and grain interiors is determined by atom probe tomography. It is found that the segregation of carbon to grain boundaries of α-ferrite can significantly reduce its grain size to a few nanometers. When the grain boundaries of ferrite are saturated with carbon, a metastable thermodynamic equilibrium between the matrix and the grain boundaries is approached, inducing a decreasing grain size with increasing xtot. Eventually the size reaches a lower limit of about 6nm in alloys with xtot>6.19at.% (1.40wt.%); a further increase in xtotleads to the precipitation of carbon as Fe3C. The observed presence of an amorphous structure in 19.4at.% C (4.90wt.%) alloy is ascribed to a deformation-driven amorphization of Fe3C by severe plastic deformation. By measuring the temperature dependence of the grain size for an alloy with 1.77at.% C additional evidence is provided for a metastable equilibrium reached in the nanocrystalline alloy.
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影响因子：
9.4
作者：
A. Michels;C. Krill;H. Ehrhardt;R. Birringer;D. T. Wu
通讯作者：
A. Michels;C. Krill;H. Ehrhardt;R. Birringer;D. T. Wu
DOI：
10.1098/rspa.1965.0158
发表时间：
1965-01-01
影响因子：
--
作者：
HONDROS, ED
通讯作者：
HONDROS, ED
影响因子：
1.6
作者：
J. Aufrecht;A. Leineweber;J. Foct;E. J. Mittemeijer;E. J. Mittemeijer
通讯作者：
J. Aufrecht;A. Leineweber;J. Foct;E. J. Mittemeijer;E. J. Mittemeijer
影响因子：
6.1
作者：
T. Ungár;J. Gubicza;G. Ribárik;A. Borbély
通讯作者：
T. Ungár;J. Gubicza;G. Ribárik;A. Borbély
影响因子：
6
作者：
X. Sauvage;W. Lefebvre;C. Genevois;S. Ohsaki;K. Hono
通讯作者：
X. Sauvage;W. Lefebvre;C. Genevois;S. Ohsaki;K. Hono