Microstructural and Mechanical Characterization of Case Carburized Steel

Abstract

In modern engineering applications, steels are extensively used owing to their versatile mechanical properties and adaptability to various heat treatment processes. Among these, case carburized steels are employed in components requiring a hard surface and tough core, such as gears, shafts, machine casings, and dies. This study focuses on the microstructural analysis and mechanical hardness characterization of low-carbon case carburized steel (0.15% C). The specimen underwent gas carburizing at 925°C for five hours, achieving a carbon-enriched surface layer of ~1 mm. Microstructural analysis at 100x magnification revealed a ferritic matrix with spheroidized pearlite, correlating with the measured surface hardness of 13–15 HRC. The study concludes that the mechanical findings align with the observed microstructural characteristics.