Effects of Processing Parameters on the Evolution of Microstructure and Hole Expansion Property of F/B Dual Phase Steels

Abstract:

With the development of auto industry, the F/B dual phase steels were widely used in wheel and underpan due to their lower cost and higher hole expansion property. In the present investigation, the effects of the finishing rolling temperature and initial cooling temperature of ultra fast cooling (UFC) on microstructure and hole expansion property of a low carbon C-Mn steel were investigated using optical microscope (OM) and scanning electron microscope (SEM). It has been found that lowering the finishing rolling temperature can refine the microstructure and the volume fraction of ferrite is increased as the initial cooling temperature of UFC is lowered. Furthermore, both lowering the finishing rolling temperature and the initial cooling temperature of UFC can improve hole expansion property.

• Periodical: Materials Science Forum (Volume 788)
• Pages: 384-389
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.788.384
• Online since: April 2014
• Authors: Xin Jun Shen, Xiang Jun Zhang, Feng Qin Ji, Jun Chen, Shuai Tang*, Guo Dong Wang
• Keywords: F/B Dual Phase Steels, Finishing Rolling Temperature, Hole Expansion Property, Start Cooling Temperature

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