"Image analysis of micrograph and fractograph for material characterization "

Abstract

Metals and alloys are extensively used for engineering applications. Strength, ductility, toughness, creep, wear or abrasion, fatigue etc. are generally considered to be some very important mechanical properties of materials in different applications. Properties of metals and alloys are governed by their micro-structures which are evolved through different thermal and mechanical processing. Hence, the study of micro-structure of metals and alloys is very important. The objective of present work is to develop image processing based automated methodologies for analysing the micro-structures of material and fracture surface. In this respect four tasks, namely (i) studying grain size distribution in the micro-structure of single phase material, (ii) measuring the volume fraction of different phases present in a material, (iii) studying micro level deformation in a single phase material and finally, (iv) studying distribution of void in a ductile fracture surface have been considered. To fulfil the objectives developing the segmentation methodologies to extract the regions of interest (grain, phase and void) is considered as the most significant task. The salient feature of the proposed image processing based methodologies is that, unlike commercial software no intervention from the end user is required. Moreover, the usage and outcome are not prejudiced by the prior acquaintance of image processing operations.