An good example of dendritic solidification, which occurs when the solidification front becomes unstable with respect to small perturbations. This results in the growth of the perturbations, producing dendrites (from the Greek for tree). The variation in colour across the micrograph indicates that the cooling was sufficiently rapid to prevent solid state diffusion and hence a concentration variation. This phenomenon is known as coring.
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.