High strength steel plate with high manganese having excellent burring workability
There is provided a high strength steel plate with high manganese having excellent burring workability, which is used for structural members, bumper reinforcing materials and impact absorbing materials of automobiles, etc. The high strength steel plate includes, by weight: C: 0.2 to 1.0%, Mn: 10 to 25%, Al: 0.3 to 3.0%, S: 0.05% or less, P: 0.05% or less, and the balance of Fe and inevitable impurities, wherein the chemical elements satisfactorily have a grain size of 18 μm or more. The high strength steel plate can be useful to facilitate formation of automobile parts since it has excellent physical properties such as elongation and hole expansibility as well as strength.
1. A high strength steel plate with high manganese comprising, by weight: C: 0.2 to 1.0%, Mn: 10 to 25%, Al: 0.3 to 3.0%, S: 0.05% or less, P: 0.05% or less, and the balance of Fe and inevitable impurities, wherein the steel has a grain size of 18 μm or more and a tensile strength*elongation (TS*El) of 50,000 MPa % or more.
2. The high strength steel plate of claim 1 , wherein the grain size is a grain size of an austenite single phase as a heat-treated structure.