Performance Comparison of Structural Steels in Chinese and American Standards

The differences and similarities in the performance and test methods of steel products commonly used in Chinese standards (GB) and American Society for Testing and Materials (ASTM) standards, GB Q235-Q460 steel in, ASTM A36(M), ASTM A572(M) steel, structural steel with atmospheric corrosion resistance and cast steel in chemical composition, yield strength, tensile strength, impact toughness, elongation after fracture and cold bending performance were compared and summarized in detail.
The analysis results show that Chinese steel standards have more detailed provisions on the chemical composition, and the welding performance is better. The yield strength of common used carbon steel and highstrength low-alloy steel decreases with the increase of the thickness of the steel plate, but the corresponding mechanical properties of the steel in ASTM will remain the same. The tensile strength of GB Q235 and Q235GJ steel is more than 6% lower than that of ASTM A36 steel. The mechanical properties of GB Q355 steel whose thickness is no more than 40 mm and GB Q345GJ steel whose thickness is no more than 50 mm are higher than those of ASTM A572GR50 steel. The mechanical properties of GB Q390 steel with thickness of no more than 40 mm and GB Q390GJ steel with thickness of no more than 100 mm are not lower than those of ASTM A572GR55 steel. The mechanical properties of GB Q420, Q420GJ, Q460 and Q460GJ steels are not lower than those of ASTM A572GR60 and ASTM A572GR65 steels respectively. The atmospheric corrosion resistance indexes of weathering steel of Chinese and American standards are both greater than 6. 0, but the chemical composition is different. The number of grades for GB weathering steel is more; the strength coverage is larger; and the mechanical properties of GB weathering steel with thickness of no more than 40 mm are not lower than those of the corresponding grade of ASTM steel. The GB cast steel has more steel grades and the coverage of strength grade is larger. The mechanical properties of cast steel specimens are different in shape and thickness, and the ASTM specimens are thicker.