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利用KKSO三维多相场模型, 在等层片宽度和厚度条件下, 研究了 CBr₄-C₂Cl₆共晶合金在不同初始层片间距条件下的三维形态演化过程、层－棒转变及三维层片间距调整机制. 研究表明, 对于亚共晶、共晶成分的CBr₄-C₂Cl₆合金, 不同的初始层片间距可能导致共晶形态发生层--棒转变, 且发生层--棒转变的趋势与初始层片间距的大小有关; 而过共晶成分的CBr₄-C₂Cl₆合金不会发生层－棒转变, 维持层片生长. 而且当无量纲初始层片间距在0.598-2.336之间变化时, 随着层片间距的增加, 其演化顺序为: 层片湮没后形成 1λO→T-xλO→1λO→2λO→分叉与形核→Z字型分叉→无序组织. 研究还表明,三维层片间距调整机制与二维层片间距调整机制类似, 基本机制为层片湮没和层片分叉. 当初始层片间距较小时, 发生层片湮没现象. 而当初始层片间距较大时, 层片发生分叉. 但由于多了第三方向的限制作用, 三维层片间距调整机制比二维复杂.

Using KKSO multi-phase field model, with equal lamellar width and thickness, three dimensional (3D) morphology evolution, lamellar-rod transition and the mechanism of adjustment of lamellar spacing of CBr₄-C₂Cl₆   alloys are investigated at different initial lamellar spacings. It's found that, as for the hypoeutectic and eutectic CBr₄-C₂Cl₆   alloy, different initial lamellar spacings may lead to lamellar-rod transition, which is related to the initial lamellar spacings. The CBr₄-C₂Cl₆   hypereutectic lamellar alloy can't transit to rod-like eutectic, with the increase of the dimensionless initial lamellar spacings Λ in the range of 0.598-2.336, the sequence of morphology evolution is: lamellar merges to form 1λO→T-xλO→1λO→2λO→lamellar branching→zigzag bifurcation$\rightarrow$lamellar destabilizes to form the disordered pattern. The simulated results also showed that the mechanism of adjustment of lamellar spacing in 3D of the CBr₄-C₂Cl₆   hypereutectic alloy is similar to that in two dimensions (2D), which is lamellar annihilation and branching on the whole, the lamellar annihilation takes place with a smaller initial lamellar spacing while the lamellar branching takes place with a bigger initial lamellar spacing. The adjustment mechanism of the lamellar spacing in 3D is more complex than that in 2D because of the additional effect of the third dimension.