10results about How to "Improve billet quality" patented technology

This invention discloses a novel bulletproof steel plate with a thickness of 12-35mm, comprising the following chemical composition by weight percentage (unit: wt%): C: 0.25-0.28, Si: 1.20-1.40, Mn: 1.50-1.60, P: ≤0.007, S: ≤0.001, Cr: 0.50-0.60, B: 0.0015-0.0023, Ti: 0.03-0.04, with the remainder being Fe and residual elements; it eliminates the need for the addition of Ni, Mo, and rare earth elements, thus reducing alloy costs. In terms of production process, clean steel smelting is used to control the P and S content, thereby improving impact toughness; pressure quenching is employed with multi-point pressure application and reasonable distribution of water volume and pressure in each section of the high-pressure zone to achieve uniform cooling and flatness of the steel plate; furthermore, low-temperature tempering is used to effectively eliminate the influence of residual internal stress in the steel plate and improve the subsequent processing performance of the steel plate, such as cutting and welding. The resulting bulletproof steel has a tensile strength of 1700-1800MPa, a surface hardness of >500HBW, and an impact energy of >40J at -20℃, which fully meets the requirements for use of bulletproof steel plates.