Hyundai Motor Company

Kia Motors Corporation

Young Joon Kang

Sung Chul Cha

Ik Soo Kim

Jun Seok Lee

Chang Hyun Shin

Disclosed herein is stainless steel having excellent tensile strength, fatigue strength, oxidation resistance at high temperature environment. According to an exemplary embodiment of the present invention, the stainless steel having excellent oxidation resistance at high temperature includes C: 0.01 to 0.2%, Si: 0.1 to 1.0%, Mn: 0.1 to 2.0%, Cr: 12.0 to 30.0%, V: 0.01 to 0.5%, Nb: 0.01 to 0.5%, Al: 0.1 to 4.0%, Co: 0.01 to 5.0%, Mo: 0.01 to 4.0%, W: 0.01 to 4.0%, B: 0.001 to 0.15%, Ni: 5.0 to 20.0% as wt %, the balance Fe, and other inevitable impurities.

Stainless steel having excellent oxidation resistance at high temperature

The present invention provides a valve for an engine and a method for treating the surface thereof. The valve for the engine includes a buffer layer, an intermediate layer, a TiAlN/CrN first nanostructured multilayer, and a TiAlCN/CrCN second nanostructured multilayer. The buffer layer is coated over a surface of a stem part as a lowermost layer and is formed of Ti or Cr. The intermediate layer is coated over the buffer layer and is formed of CrN, TiN, or TiCN. The TiAlN/CrN first nanostructured multilayer is coated over the intermediate layer. The TiAlCN/CrCN second nanostructured multilayer is coated over the TiAlN/CrN first nanostructured multilayer as an uppermost layer.

Growing community of inventors

Seoul, South Korea

Young Joon Kang