Experimental Study on the Forming Limit Diagram of QP980 under Variable Pressing Velocities

Abstract:

QP steel has great application potential for automotive industry for its ultrahigh strength and good plasticity. In this paper, the forming limit diagram (FLD) of QP steel was experimentally studied using spherical punch test. The forming limit curves (FLC) of QP steel in room temperature under two pressing velocities (20mm/s, 2mm/s) were obtained. It has been found that the deformation velocity affects the FLC obviously; the FLC declines with the increase of pressing velocity. Compared with other AHSS under the same strength grade, QP steel keeps high strength without a significant loss of plasticity.

• Periodical: Applied Mechanics and Materials (Volumes 275-277)
• Pages: 1870-1873
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.275-277.1870
• Online since: January 2013
• Authors: Lei Ding, Jian Ping Lin, Zheng Pang
• Keywords: AHSS for Automobile, FLD, QP Steel, Velocity

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