Dendritic cell-size - its growing importance

Abstract

Dendritic cell size is hereby proposed to be the basic parameter in mechanism of solidification, and grain size is a manifestation of orienta ion of cells, The technique of anodic oxidation etching has been developed to reveal dendritic cells distinctly in as-cast and homogenized states of Al and binary alloys of Al-Ca, Al-Mn and Al-Mg. The effect of pouring and solidification temperatures on cell size has been determined. The temperature of 700°C has been found to be the critical pouring temperature for obtaining uniform cell size in Al and At-Mn, Al-Mg alloys, irrespective of the degree of supercooling. Duplex cell size was observed in chill-east Al-Mg alloys and the effect of heating at 500°C for 8, 16 and 24 hours on cell size has been demonstrated with the help of anodized photomicrographs