Akademik Veri Yönetim Sistemi
International Journal of Metalcasting, 2025 (SCI-Expanded)
Austempered ductile iron (ADI) is widely employed in applications that demand high strength, wear resistance, and toughness, and its properties can be tailored through controlled alloying and heat treatment. In this study, the influence of varying copper content on the microstructure and mechanical performance of ADI processed via austempering, deep cryogenic treatment, and tempering was investigated. Samples were categorized into three groups: Group A (as-cast), Group B (austempered and deep cryogenically treated at −196 °C for 6 h), and Group C (austempered, deep cryogenically treated at −196 °C for 6 h, followed by tempering at 280 °C for 2 h). The austempering process involved heating samples to 900 °C for complete austenitization, quenching in a salt bath at 300 °C, and holding for 2 h. Microstructure of the samples were characterized using optical microscopy and X-ray diffraction, while mechanical properties such as hardness, impact toughness, and tribological performance were evaluated. The results demonstrated that copper addition significantly enhances hardness and wear resistance by promoting the transformation of austenite into ausferrite. Deep cryogenic treatment further facilitates martensitic transformation, improving wear resistance by up to 15–20%. Although cryogenic treatment results in a modest increase in hardness (2–3 HRC), subsequent tempering slightly reduces hardness (1–5 HRC) but significantly improves impact toughness by alleviating brittleness. These results highlighted the critical role of copper alloying and advanced thermal treatments in optimizing ADI's microstructure and mechanical performance for high-performance applications.