Journal of Failure Analysis and Prevention

, Volume 12, Issue 5, pp 518–531 | Cite as

Effect of Mechanical Cut-Edges on the Fatigue and Formability Performance of Advanced High-Strength Steels

Technical Article---Peer-Reviewed

Abstract

Mechanical cut-edge properties influence the fatigue lives and formability capacity of advanced high-strength steels. This factor is critical as S355MC and DP600 exhibited an increased sensitivity to fatigue cracks initiating from defects on the cut-edge fracture zone. Mechanical cut-edges as a result displayed a decreased level of formability that was highly dependent on the cut-edge surface and internal microstructure of the cut-edge produced. It was determined that, by controlling the mechanical clearance, optimized mechanical cut-edges were produced. This was achieved through minimizing surface damage and by controlling the internal and topographical properties of the cut-edge zones.

Keywords

Cut-edge fatigue Automotive manufacturing Forming Hole expansion capacity 

Nomenclature

A

Elongation to failure

AHSS

Advanced high-strength steel

HEC

Hole expansion capacity

HSLA

High-strength low alloy

HV

Vickers hardness

MPa

Mega Pascal

R

Stress ratio (min stress/max stress)

Ra

Arithmetic mean of departures from the mean line

Rp

Maximum height of profile above the mean line

Rv

Maximum depth of profile below the mean line

S-N

Stress-life

Wt

Weight

Notes

Acknowledgments

The present research was funded by a grant from the Engineering and Physical Sciences Research Council (EPSRC). The author wishes to thank the support of Swansea University College of Engineering and the Engineering Centre for Manufacturing and Materials during the pursuit of this research.

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Copyright information

© ASM International 2012

Authors and Affiliations

  1. 1.Materials Research Centre, College of Engineering, Swansea UniversitySwanseaUK

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