Region Growth Based Segmentation to Improve the Porosity of Cu - (5–20%) W Composite Preforms

While preparing the composite preform in the powder metallurgy Lab, the various defects due to porosity, open crack and residual stresses are possible. This may lead to poor life and strength of materials. It is difficult to predict the defects in the form of pores physically in the powder metallurgy Lab. To simplify this kind of problem, the Scanning Electron Microscope (SEM) images are generated from the powder composites and are segmented using region growth approach to find the distribution of pores. Normally, the composite preforms are being produced through various processes like mechanical milling, mixing, compaction, sintering and hot extrusion. In this study, Cu–(5–20%) W composite preforms, with a preform density of 94% are prepared. The pore size in term of coverage area, perimeter during different sintering atmospheres are derived. Further, the porosity is reduced during extrusion process. The results of SEM images are compared before and after sintering and extrusion process. This kind of work will aid the manufacturing process of material parts in predicting their strength and life time. KeywordsImage segmentation, Region growing, composites, porosity analysis