Solidification eutectic lamellae

More recent extensions of the theory (see citations in [122]) gave indications that the orientation of the lamellae (under isotropic material parameters) is not necessarily parallel to the growth direction of the front but may be tilted so that the lamellae travel sideways at some specific angles [138]. Finally it was found that the standard model of eutectic solidification has an intrinsic scaling structure [141-147]... 

The orientation of the lamella tends to be along the direction of heat flow. In polycrystalline grains solidified from a melt of eutectic composition, the orientation is more or less random but the spacing of the lamella is indicative of the rate the material was solidified. However, if a eutectic composition is directionally solidified, the lamella will be aligned along the solidification direction to form what is known as an in situ composite. If the eutectic system happens to be a low volume fraction eutectic (the eutectic composition is such that A B or vice versa), the minority phase will form a rod-like structure rather than the lamella structure described above. The spacing of the rods will still be governed by the... 

A major method of controlling solidification porosity is directional solidification. Such solidification of eutectics results in unidirectional leunellar or rod "reinforced" composites, wherein the thickness of the lamellae or rod diameters are inversely proportional to the solidification... 

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