根据0点阵理论计算了fcc/bcc和fcc/bct在三种取向关系时的0点阵单胞体积V~(0).按V~(0)越大,该取向越稳定的判据,得知不同取向关系有各自合理存在的γ值范围。当γ值取某些特定值,就出现能量最低的二维0线点阵。业已提出,溶质原子可能局部偏析或贫化,使界面处γ值发生变化而降低界面的位错密度。α/β黄铜中Zn的偏析可以用这个模型加以解释。 业已表明,四方畸变的大小和方向对V~(0)影响显著。如果已知fcc/bct的取向关系,就可以预示合理的畸变方向。但是,要说明Fe-C合金中取向关系由K-S转变成N-W的事实,得假定碳原子偏析到界面内的<11(?)>_f方向。
The cell volume V~((0)) of fcc/bcc and fee/bet has been calculated for three orientation relationships. The orientation will be acceptable if its V~((0)) is larger than others, and everyone has its own range of lattice parameter ratio. Then the lower energy 0 lattice will appear when γ gets some particular value. It is suggested that the γ value can be changed locally by segregating or depleting solute atoms near boundary so that the density of dislocation on boundary can be decreased. The Zn segregation in α/β brass would be explained with this mode.It is shown that the magnitude and direction of tetragonal distortion affect the V~((0)) considerably. It will be expected to predict the reasonable distortion direction if the orientation and the lattice parameter are given. But the fact that the orientation relationship between austenite and martensite in Fe-C alloy changes from K-S to N-W can be explained satisfyingly if it is suggested that carbon atoms move to transformation interface along <11(?)>_f direction.
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