Dendrite morphology of several steady state unidirectionally solidified iron base alloys

Abstract

The experimental data are presented of the dendrite morphology of steady state unidirectionally solidified steels. The dendrite arm spacings were correlated with the equation A =KR mGmwhereR is the growth rate and G the temperature gradient. The exponentsm andn for the primary arms are fairly close to the theoretical values (m = -0.25,n = -0.5). For the secondary arms they are about the same (-0.4). The primary arm spacings do not depend much on composition. The secondary arm spacings, however, decrease at fixed carbon content with increasing content of substitutional elements, and they were found to be smaller in a steel freezing as ferrite compared to steels freezing as austenite.