The strengthening mechanisms in metals mainly include solid solution strengthening, dislocation strengthening, fine grain strengthening, and second phase (precipitation and dispersion) strengthening. Alloying elements have the most significant strengthening effect on steel in the quenched and tempered state, because it makes full use of all four strengthening mechanisms. Martensite is formed during quenching, and carbides are precipitated during tempering, resulting in a strong second phase strengthening and greatly improving toughness. Therefore, obtaining martensite and tempering it is the most economical and effective comprehensive strengthening method for SA514 Grade B plate cost.
S355J2+N steel plate belongs to the European standard low alloy structural steel grade. S355J2 steel is equivalent to Q345D grade. SA514 Grade B plate cost, S355J2+N low alloy steel plate is widely used in bridges, vehicles, ships, building steel structures. Mechanical properties of S355J2+N steel: Yield strength: ≤16mm: ≥355; 16-40: ≥345; 40-63: ≥335; 63-80: ≥325;80-100: ≥315; 100-150: 295; 150-200: ≥285; 200-250: ≥275; 250-400: ≥265. Tensile strength: 450-680MPa.
In October, steel production decreased month-on-month, port inventories continued to rise, iron ore demand intensity weakened slightly, and iron ore prices continued to fall. According to the monitoring of the China Iron and Steel Industry Association, at the end of October, the China Iron Ore Price Index (CIOPI) was 421.41 points, down 11.06 points month-on-month, or 2.56%. The month-on-month decline continued, with a decrease of 0.08 percentage points higher than in September.