Gm Global Technolgoy Operations, Inc.

Northeastern University

Zhisong Chai

Wei Xu

Jianfeng Wang

Qi Lu

Congjie Wang

Zhou Wang

JinLong Zhu

Tingdong Ren

A coated steel sheet includes a steel sheet comprising iron (Fe); carbon (C) in a range from 0.05% to 0.35 wt. %; manganese (Mn) in a range from 0.1% to less than 2 wt. %; chromium (Cr) in a range from 1.2% to 6.0 wt. %; silicon (Si) in a range from 0.01% to less than 0.6 wt. %; aluminum (Al) in a range from 0.5% to 1.3 wt. %; vanadium (V) in a range from 0.01% to 0.5 wt. %; niobium (Nb) in a range from 0.01% to 0.2 wt. %; and titanium (Ti) in a range from 0.01% to 0.3 wt. %. A zinc coating is formed on an outer surface of the steel sheet.

Hot dip galvanized ultra-high strength steel sheets with high flatness

A method for preparing a press-hardened steel component is provided. The method includes forming a heated blank by heating a steel alloy blank to a first temperature in a first zone of a furnace having two or more zones, and after the heating of the steel alloy blank to the first temperature, heating the steel alloy blank to a second temperature in a second zone of the furnace. The second temperature is greater than the first temperature. The first zone has a first flow rate for a protective gas, and the second zone has a second flow rate for the protective gas that is greater than the first flow rate. The method further includes stamping and quenching the heated blank at a constant rate to a temperature between a martensite finish temperature of the steel alloy defining the steel alloy blank and room temperature to form the press-hardened steel component.

Methods for preparing high performance press-hardened steel components

A method of forming a component includes providing a work-piece blank from a formable material. The work-piece blank includes at least one section having a surface roughness greater than 1 &#x3bc;m configured to facilitate efficient radiation of thermal energy therefrom when the work-piece blank is heated. The method also includes austenitizing the work-piece blank via heating the work-piece blank at a predetermined temperature for a predetermined amount of time to achieve an austenite microstructure in the at least one section and forestall oxidation of the work-piece blank. The method additionally includes transferring the austenitized work-piece blank into a forming press. The method also includes forming the component via the forming press from the austenitized work-piece blank. The method additionally includes quenching the component formed from the austenitized work-piece blank and cooling the formed component.

Stamped components with reduced hot-forming cycle time

Growing community of inventors

Shanghai, China

Zhisong Chai