Arcelormittal

Arcelormittal Investigacion Y Desarrollo, S.l.

Juan David Puerta Velasquez

Pascal Drillet

Jonas Staudte

Sebastian Cobo

Martin Beauvais

Catherine Vinci

A cold-rolled sheet is provided. The cold-rolled sheet includes a steel substrate with a carbon content Cbetween 0.07% and 0.5%, expressed by weight, and a metal pre-coating on at least the two principal faces of the steel substrate. The substrate has a decarburized area on the surface of each of the two principal faces. The depth pof the decarburized area is between 6 and 30 micrometers, and pis the depth at which the carbon content is equal to 50% of the content C. The sheet does not contain a layer of iron oxide between the substrate and the metal pre-coating.

Precoated sheets for manufacturing press-hardened coated steel parts

A cold-rolled sheet is provided. The cold-rolled sheet is annealed and pre-coated for the fabrication of press hardened parts, composed of a steel substrate for heat treatment with a carbon content Cbetween 0.07% and 0.5%, expressed by weight, and a metal pre-coating on at least the two principal faces of the steel substrate. The substrate comprises a decarburized area on the surface of each of the two principal faces. The depth pof the decarburized area is between 6 and 30 micrometers, and pis the depth at which the carbon content is equal to 50% of the content C. The sheet does not contain a layer of iron oxide between the substrate and the metal pre-coating. Processes are also provided.

Process for manufacturing press-hardened coated steel parts and precoated sheets allowing these parts to be manufactured

The present invention provides a rolled steel sheet, for press hardening, for which the chemical composition includes, with contents expressed by weight, 0.24%&#x2266;C&#x2266;0.38%, 0.40%&#x2266;Mn&#x2266;3%, 0.10%&#x2266;Si&#x2266;0.70%, 0.015%&#x2266;Al&#x2266;0.070%, 0%&#x2266;Cr&#x2266;2%, 0.25%&#x2266;Ni&#x2266;2%, 0.015%&#x2266;Ti&#x2266;0.10%, 0%&#x2266;Nb&#x2266;0.060%, 0.0005%&#x2266;B&#x2266;0.0040%, 0.003%&#x2266;N&#x2266;0.010%, 0.0001%&#x2266;S&#x2266;0.005%, 0.0001%&#x2266;P&#x2266;0.025%, it being understood that the titanium and nitrogen content satisfy: Ti/N&#x3e;3.42, and that the carbon, manganese, chromium and silicon content satisfy: with the chemical composition optionally including one or more of the following elements: 0.05%&#x2266;Mo&#x2266;0.65%, 0.001%&#x2266;W&#x2266;0.30%, 0.0005%&#x2266;Ca&#x2266;0.005%, with the remainder made up of iron and inevitable impurities coming from preparation. The sheet includes a nickel content Niat any point of the steel near the surface of said sheet over a depth &#x394;, such that Ni&#x3e;Ni, where Nidesignates the nominal nickel content of the steel, and such that Nidesignates the maximum nickel content within &#x394;: and such that: with the depth &#x394; expressed in microns and the Niand Nicontents expressed in percentages by weight.

Growing community of inventors

Metz, France

Juan David Puerta Velasquez