ADAPTIVE PHASE FORMATION IN MARTENSITIC-TRANSFORMATION
ADAPTIVE PHASE FORMATION IN MARTENSITIC-TRANSFORMATION
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DOI：
10.1103/physrevb.43.10832
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发表时间：
1991-05-01
影响因子：
3.7
通讯作者：
SEMENOVSKAYA, S
中科院分区：
文献类型：
--
作者：
KHACHATURYAN, AG;SHAPIRO, SM;SEMENOVSKAYA, S
它示出的外观的中间马氏体相称为自适应马氏体可以预期，如果正常马氏体相的两个取向变体之间的边界的表面能是非常低的，典型的晶格失配相关的弹性能是高的。 自适应马氏体形成为弹性约束相时，由晶体应变调节引起的结构不均匀性的规模减少到与孪晶面间距相称的微观尺度。 一个例子的立方-> tetraxite变换被认为是自适应相位具有伪正交晶格。 通过母相立方相和四方马氏体的晶格参数来表示自适应相的晶格参数。 结果表明，β 'NiAl合金中的（5，2BAR）7 R马氏体和最近在Fe-Pd合金中发现的高于fcc → fct马氏体相变温度的中间相是适应马氏体的例子。 讨论了自适应相在马氏体热形核中的可能作用。 正常马氏体的成核可以被自适应相的成核绕过，自适应相在生长期间转变为正常马氏体。
It is shown that an appearance of an intermediate martensite phase called adaptive martensite may be expected if the surface energy of a boundary between two orientational variants of the normal martensite phase is very low and the typical lattice-mismatch-related elastic energy is high. The adaptive martensite is formed as an elastically constrained phase when the scale of structure heterogeneities induced by the crystal-strain accommodation is reduced to the microscopic scale commensurate with the twin-plane interplanar distance. An example of the cubic --> tetragonal transformation is considered where the adaptive phase has a pseudo-orthorhombic lattice. The crystal-lattice parameters of the adaptive phase are expressed through those of the parent cubic phase and tetragonal normal martensite. It is shown that the (5,2BAR)7R martensite in beta'NiAl alloys and the intermediate phase recently found just above the temperature of the fcc --> fct martensitic transformation in Fe-Pd are examples of the adaptive martensite. A possible role of the adaptive phase in the thermal nucleation of the martensite is discussed. The nucleation of the normal martensite may be bypassed by nucleation of the adaptive phase, which transforms to the normal martensite during the growth.