Patent ID: 10385415

Abstract:
Methods of strengthening surface regions of high-strength transformation induced plasticity (TRIP) steel are provided. The method may comprise shot peening at least one region of an exposed surface of a hot-formed press-hardened component comprising a high-strength steel. Prior to shot peening, the component has a microstructure comprising ≥ about 5% by volume retained austenite in a matrix of martensite. The shot peening is conducted at a temperature of ≤ about 150° C. and forms at least one hardened surface region comprising ≤ about 2% by volume austenite. The TRIP steel may be zinc-coated and having a surface coating comprising zinc and substantially free of liquid metal embrittlement (LME). Zinc-coated hot-formed press-hardened components, including automotive components, formed from such methods are also provided.