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本文用X射线衍射方法研究电沉积Ni-P合金的结构。研究表明:当P含量小于5.4at%时合金为P在Ni中的过饱和固溶体;当P含量大于7.8at%时结构发生明显变化,衍射花样可解释成一些大小为6—8?的密堆小片。它们作平行而无规的相对错动,片间距为2.04?,堆垛成小柱状,柱高随含P量的增高而减小,从含P为7.8%时的124?降到含P为18%时的13?,成为典型的非晶态合金的衍射花样。利用{lll}谱线的强度比,或者用原子径向分布函数的峰形和峰高,估算出原子偏离平衡位置的均方根值为0.17?。由于这些扭曲,使层间距在小于原子直径的情况下仍能实现片与片间相对平行而无规的错动,而且使一个小柱能够直接过渡到另一个取向不同的小柱而无须形成晶界。所以样品是一个连续分布的整体而不是一个微晶的集合体。另外,还测量了{lll}谱线不同衍射级的宽度。发现βlll/β222lll/cosθ222,或许线宽除受垛高因素所制约外,可能还与成份起伏、微应变以及片层间距轻微的不规则性有关。The structures of electrodeposited alloy of nickelphosphorus system were investigated by means of X-ray diffraction, method. It is shown that the structures of those alloy are a solid solution of phosphorus in nickel while the contents of phosphorus are less than 5.4 at%. When the contents of phosphorus increase up to more than 7.8 at%, the structures of alloys suffer a tremendous change, the diffraction patterns of these alloys may be interpreted by a model of random-layer (turbostratic) structures. The distances between neighbouring layers are 2.04? and the diameter of the layers are 6-8?. The thickness of stacking of layers is decreased as the contentes of phosphorus in alloy are increased. For examples, it changes from 124? for 7.8 at% P to 13? for 18 at% P. The diffraction pattern of the later is just the same as that of the typical amorphous alloys.Using the data of the ratio of intensities of {lll} or the data of the radial distribution function, the rootmean-square of static distortion can be calculated as (u2)1/2=0.17?. This value can be used to interpret why an arbitrary displacement between two neighbouring layers would be possible even though the distance between neighbouring layers is smaller than the diameter of an atom. Because of the small dimension of the layers and the large static distortion of the atom, it is easy to change the orientation of layer domain and no cr-ystallographic boundary region are necessary for the variation of orientation, so that the specimens are the continue distribution of atoms as a whole bat not an aggregation of micro-crystals.The β{lll} corresponding to the breadth of {lll} reflection at half-maximum intensity have been measured for some specimens. The results show that βlll/β222222/cosθlll, where θ is the Bragg angle, this means there would be some other factors (for example, the component fluctuation), to affect the breadth of the reflection line, besides the size factor.
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