Fracture toughness of austempered chilled ductile iron

✍ Scribed by Joel Hemanth

• Publisher: Elsevier Science
• Year: 1998
• Weight: 159 KB
• Volume: 19
• Category: Article
• ISSN: 0261-3069
• DOI: 10.1016/s0261-3069(98)00037-5

✦ Synopsis

The structure and properties of ductile iron are highly dependent on the solidification mechanism and chills are used to promote directional solidification to get sound castings. A series of fracture toughness experiments were carried out involving austempered chilled ductile iron containing 3.42% C, 1.8% Si and other alloying elements. By using copper chills of different thickness, the fracture toughness of varying the chill rate was also examined. The fracture toughness tests were carried out using three-point bend specimens, each with a chevron notch, as per ASTM E 399 1990 standards. It was found that austempered chilled ductile iron is highly dependent on the location on the casting from where the test samples are taken and also on the Ni and Mo content of the material. Chill thickness, however, also affects the fracture toughness of the material.