Ultrafine Grained Dual Phase Steels Fabricated by Equal Channel Angular Pressing

Abstract:

Ultrafine grained (UFG) ferrite-martensite dual phase steels were fabricated by equal channel angular pressing and subsequent intercritical annealing. Their room temperature tensile properties were examined and compared to those of coarse grained counterpart. The formation of UFG martensite islands of ~ 1 μm was not confined to the former pearlite colonies but they were uniformly distributed throughout UFG matrix. The strength of UFG dual phase steels was much higher than that of coarse grained counterpart but uniform and total elongation were not degraded. More importantly, unlike most UFG metals showing negligible strain hardening, the present UFG dual phase steels exhibited extensive rapid strain hardening.

• Periodical: Materials Science Forum (Volumes 503-504)
• Pages: 447-454
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.503-504.447
• Online since: January 2006
• Authors: Dong Hyuk Shin, Woo Gyeom Kim, Jung Yong Ahn, Kyung Tae Park, Yong Suk Kim
• Keywords: Dual Phase Steel, Equal-Channel Angular Pressing (ECAP), Strain-Hardening, Ultrafine Grained

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