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3706198 
Book/Book Chapter 
A New Invention of Press-hardened Steel Achieving 1880 MPa Tensile Strength Combined with 16% Elongation in Hot-Stamped Parts 
Yi, HL; Du, PJ; Wang, BG 
2015 
CHS2-Series 
5 
725-734 
WOS:000372941900073 
An obvious weakness of current press-hardened steels (PHS) is their poor toughness, meanwhile, 1500 MPa is no longer a securely high strength for PITS to complete with cold-formable steel counterparts. For these reasons, attempts to develop higher strength PHS with improved elongation are being made worldwide. In this report, we present a new PHS achieving 1880 MPa ultimate strength, 1400 MPa yield strength and 16% elongation in final formed parts. The steel chemistry was designed on the basis of medium manganese addition which allows to lower austenization temperature, stabilize austenite and improve hardenability. After hot stamping, an extra tempering could dramatically enhance the ductility. However, this quenching and tempering process is not for a carbide forming purpose, instead, the tempering aims to enhance austenite quantity and stability, which is based on the quenching and partitioning (Q&P) concept. In addition to the obviously attractive mechanical properties, the advantages of the new PHS proposed in this report include lower austenization energy consumption, possibility to be zinc coated and low impact for current PHS line.