Novel cold-rolled martensitic ultra-high-strength steels for roll forming technologies

Abstract

Roll forming is one of the fastest developing forming technologies for martensitic ultra-high-strength steels in the automotive industry. As the automotive industry continues to demand materials exhibiting higher strength in addition to improved formability, development of novel martensitic ultra-high-strength steels for roll forming technologies is a priority topic in the steel industry. Six such novel steels were developed, exhibiting ultimate tensile strength from 1500 to 2000 MPa, total elongation from 4% to 11%, bend ratio from 5t to 2t and hole-expansion capacity from 18% to 80%. It was concluded that the novel steels exhibit very attractive properties for roll forming technologies and provide low cost down-gauging opportunities with improved crashworthiness for the automotive industry.

Keywords

Continuous annealing Martensite Roll forming Automotive

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