DEVELOPMENT OF A DIGITAL SEM-BASED FRAMEWORK FOR QUANTITATIVE PHASE ANALYSIS OF CARBIDIC AUSTEMPERED DUCTILE IRON AT 375°C
Srinuvasu.N1, Dr. Mahendra. K. V.2, Dr. M.K. Muralidhra3, Dr. Gangadhar N.4, Ratika M.5, Dr. Ramprasad6
1VTU Research Scholar, 2,3Professor, Mechanical Department, RR Institute of Technology, Bangalore – 90, India
1,4,5,6Assistant Professor, Mechanical Department, Dr. Ambedkar Institute of Technology, Bangalore – 56, India
Abstract: Carbidic Austempered Ductile Iron (CADI) offers a unique combination of high strength and wear resistance, yet the fundamental relationship between austempering parameters and the resulting phase morphology remains a critical area of investigation. This study specifically examines the microstructural evolution of CADI through high-resolution Scanning Electron Microscopy (SEM). By varying the austempering temperature and isothermal holding time, the transition from upper to lower ausferrite was mapped alongside the distribution of pro-eutectic carbides. SEM analysis reveals the critical role of the carbide-matrix interface and the refinement of acicular ferrite in dictating abrasive wear performance. Quantitative image analysis was employed to correlate the volume fraction of retained austenite with processing variables, providing a localized perspective on how austempering triggers microstructural transformations. The findings establish a direct link between sub-micron structural features and the macroscopic mechanical integrity of CADI.
Keywords: Scanning Electron Microscopy (SEM), Microstructural Evolution, Carbidic Austempered Ductile Iron (CADI), Ausferrite Morphology, Phase Transformation, Image Analysis.
VOLUME 10 ISSUE 08 2026: 78 – 86