Low Temperature Hot Press Forming of a Zinc Coated Third Generation Advanced High Strength Steel

Abstract:

A 7 wt.% Mn steel was designed and was cast and processed to 1.5 mm sheets. The sheets were continuous annealed and coated with a Zn alloy by hot dip galvanizing before subjecting them to hot press forming cycles. The final microstructure was characterized by ultrafine ferrite grains and a high fraction of retained austenite. Excellent combinations of in-service strength-ductility-bendability were achieved for hot forming in the temperature range of 530-675 °C. The use of the low temperature hot forming minimized the liquid metal embrittlement induced cracking with Zn coating during hot forming and spot welding. Various application properties such as oxidation resistance, corrosion resistance, and springback were found at optimum levels for hot forming at 675 °C.

• Periodical: Materials Science Forum (Volume 1105)
• Pages: 225-230
• DOI: https://doi.org/10.4028/p-uDks6S
• Online since: November 2023
• Authors: Radhakanta Rana*, Theo Kop, Peter Beentjes, Ellen van der Aa
• Keywords: Liquid Metal Embrittlement, Low Temperature Hot Forming, Medium Manganese Steel, Residual Formability, Zinc Coating

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