Metallurgical Evaluation and Failure Analysis of Cracking in Wheel Rim SPFH590 Steel

Manufacturing wheel rims in the automobile industry demands high quality, high production, cost-effective and flawless wheels. At present, JIS G3138 SPFH 590 steel is widely used for manufacturing wheel rims for light and medium commercial vehicles. For high productivity, Flash butt welding is used for joining the edges of hot rolled strips. Cracking in wheel rims is a significant problem encountered in the production sectors. The present study is aimed at evaluating failure types in wheel rims by factors governing flash butt weld and subsequent cold forming processes. The microstructure of fractured specimens was examined by field emission scanning electron microscopy (FESEM) and an optical microscope. The mechanical characterization was analysed by tensile tests and crack tip opening displaced testing. The outcome of the results obtained was correlated with metallurgical concepts in order to find the cause of cracking failure.