Fracture behaviour of Compositionally graded steels (CGS)

There is currently much interest in the design and utilization of hybrid materials and laminated materials in which the outer regions and the core of the material have different combinations of properties. In steels, variation of the carbon content by means of selective carburization or decarburization can be used to produce hybrid materials. The current results show that new combinations of high strength and fracture resistance can be achieved by this metal. The fracture behaviour was investigated for a variety of microstructures with a hard core (e.g martensite or pearlite) and softer outer layer (bainite or ferrite). The improvement in fracture strain due to the presence of the outer layer was investigated under tensile conditions.