GB/T1591 Q390A steel is high strength low alloy steel material. "Q" is the first letter of Chinese Pinyin: "qu fu dian", that means Yield Point, "390" is the minimum value of yield strength 390 MPa for steel thickness 16mm. "A" is the quality level. According to GB/T 15912008, Q390 material has 5 quality grades: Q390A, Q390B, Q390C, Q390D and Q390E. low alloy steel specification: Shapes: plates, sheet, angle, channel and round bar Thickness : 1.5-300mm Width: 1220-4200mm Length : 5000-18000mm Notes: coil thickness up to 25mm
