Application of the disector to determine the distribution of true interlamellar spacing in lamellar microstructures

Abstract

It is well known that the interlamellar spacing controls the mechanical properties of any material with a lamellar microstructure. It is also expected, although not yet established, that varying distribution of interlamellar spacing would also influence the properties. However, the problem of determining the distribution of interlamellar spacing from metallographic observations made on single 2D sections is almost intractable. A technique to estimate the true interlamellar spacing in a lamellar microstructure, using a 3D probe referred to as a disector, has been developed. This disector technique was used to obtain the distribution of true interlamellar spacing of pearlite in a microalloyed steel. The results indicate clearly that there is a significant variation of interlamellar spacing across pearlite colonies and also within individual colonies. In addition, it was possible to determine the overall distribution of interlamellar spacing.