Patent · US Active

Press hardened steel with surface layered homogenous oxide after hot forming

US11530469B2 · kind B2 · utility

1Cited by

65References

17Claims

0Family size

Assignee

GM GLOBAL TECHNOLOGY OPERATIONS LLC · US

Inventors

Qi Lu · Zhejiang, CN
Jianfeng Wang · 安丰镇, CN

Key dates

Filing date	Jul 2, 2019
Grant date	Dec 20, 2022
Priority date	—
Expiry date	Aug 13, 2039

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC22C2204/00
WIPO fieldMaterials, metallurgy
WIPO sectorChemistry

Abstract

A press-hardened steel is provided. The press-hardened steel has an alloy matrix including from about 0.01 wt. % to about 0.35 wt. % carbon, from about 1 wt. % to about 9 wt. % chromium, from about 0.5 wt. % to about 2 wt. % silicon, and a balance of iron. The alloy matrix is greater than or equal to about 95 vol. % martensite. A first layer is disposed directly on the alloy matrix. The first layer is continuous, has a thickness of greater than or equal to about 0.01 μm to less than or equal to about 10 μm, and includes an oxide enriched with chromium and silicon. A second layer is disposed directly on the first layer, and includes an oxide enriched with Fe. Methods of preparing the press-hardened steel are also provided.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.