A critical review on fractographic studies of steel cord and bead wire used in tyre reinforcement

Fracture is one of the failure modes of a material or product which may occur during its manufacturing process or its usage. Fractography is the science and art of examination and analysis of the fractured surface. Texture and nature of the fractured surface provide valuable information on origin of a crack and crack propagation; thereby, it helps to understand the mechanism of fracture and facilitate to identify the likely causes of failure. This review covers an extensive study on various types of fractures of steel cord and bead wire which are primarily used in rubber composites viz tyre, conveyor belt etc. Different types of fractures studied include ductile, central burst, brittle, fatigue, torsion, corrosion, delamination and weld fractures. Fundamentals on specific characteristics of each type of fracture and their likely causes have been elaborately discussed Microscopic examination through scanning electron microscope (SEM) provides deeper insights of the fractured surface as well as microstructure of material. In addition to the fundamental aspects of fractures, examples of different types of fractured samples have been illustrated in this article. This focused review would be useful to the steel cord and bead wire manufactures as well as to tyre manufacturers for detailed failure investigation of material/product and thereby to take appropriate corrective measures.