XLVIII. X-ray study of some meteoric irons
XLVIII. X-ray study of some meteoric irons
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四十八．
DOI：
10.1080/14786443908521237
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发表时间：
1939
期刊：
影响因子：
--
通讯作者：
B. Burns
中科院分区：
文献类型：
--
作者：
B. Burns
在对人工制备的铁镍合金的结构进行X射线分析的详细研究过程中，人们发现制备处于完全热平衡状态的富铁合金是极其困难的。长时间的热处理是必要的，并且在进行热处理时必须采取某些预防措施（%鉴于这些合金所经历的困难，决定对流星铁的结构进行研究，希望这种材料可以提供有用的信息关于铁镍合金中普遍存在的平衡条件。陨铁可分为两大类：镍含量低于6%的陨铁，含镍量较高的矿物具有较复杂的三种组分结构，其中有些矿物具有被称为威德曼图的特征图形。三种成分是：（a）kamacite，相当于纯铁镍合金中的~-相;（B）t_enite，相当于纯y相;（c）plessite，可能由kamacite和t_enite的微观八面体排列组成，也可能是粒状的，在显微镜下没有明确的结构。这项调查也可能揭示一些关于铁陨石的构成和结构的争议点。关于任何一种陨石中两种成分--铁纹岩和铁纹岩的成分的恒定性，以及各种陨石中这些成分的成分的变化（如果有的话），如铁纹岩带宽度不同的Widmanst~ tten图案，都将受到欢迎。了解天然合金在多大程度上符合从相同成分的人造合金研究中获得的现有知识也是有意义的。
IN the course of a detailed study by X-ray analysis of the structure of artificially prepared iron-nickel alloys, it was discovered that it was extremely difficult to prepare alloys rich in iron, which were in a state of complete thermal equilibrium. Prolonged heat treatments were necessary, and certain precautions had to be taken in carrying out the heat treatments (% In view of the difficulties experienced with these alloys, it was decided to make a study of the structure of meteoric iron in the hope that this material might furnish useful information concerning equilibrium conditions existing in iron-nickel alloys generally. Meteoric irons may be divided into two main groups; those with nickel content below about 6 per cent., containing only one constituent (kamacite), and those of higher nickel content possessing a more complex structure of three separate constituents and in some of which are found characteristic patterns known as Widmanst~ tten figures. The throe constituents are:(a) kamacite, which corresponds to the~-phase in the pure iron-nickel alloys;(b) t~ enite, corresponding to the pure y-phase; and (c) plessite, which may consist of a microscopic oetahedral arrangement of kamacite and t~ enite or may be of a granular nature, showing no definite structure under the microscope. The investigation might also shed some light on certain points in dispute concerning the constitution and structure of iron meteorites. Information would be welcomed concerning the constancy of the compositions of the two constituents, kamacite and t~ enite, in any given meteorite, and the variation, if any, in the composition of these constituents in various meteorites which show, for example, Widmanst~ tten patterns with kamacite bands of different widths. It is also of interest to know how far the natural alloys conform with existing knowledge derived from the study of artificial alloys of the same composition.