Effect of Austempering Times on the Microstructures and Mechanical Properties of Dual-Matrix Structure Austempered Ductile Iron (DMS-ADI)

In this study, the effect of austempering times on microstructures and mechanical properties dual-matrix structure austempered ductile iron (DMS-ADI) was investigated. With aim, unalloyed as-cast tensile samples were austenitized at 810 °C for 30 min to intercritical austenitizing followed by 350°C various (45 180 min). Experimental results showed that structures consisting proeutectoid ferrite + ausferrite obtained in from temperatures. It determined as time increased, ausferritic became considerably clear its volume fraction almost constant (45–47%) after 90 time. The yield strength decreased total elongation breaking energy increased with increasing times, but 120-min time, both decreased. established had no significant morphology ausferrite. best between 70- 130-minute can be defined processing window. addition, it DMS-ADI similar kinetics ADI.