Type Of Q235 Carbon Steel

Carbon structural steel Q235 in GB/T 700-2006 is divided into four grades A, B, C and d according to metallurgical quality.

Q235 is a quality grade symbol. The quality grades of deoxidation method symbols are a, B, C and D. the quality of Grade A is poor, and the quality of grade D is the highest. The symbols of deoxidation method are f, B, Z and TZ, which respectively represent boiling steel, semi killed steel, killed steel and special killed steel. However, the symbols of Z and TZ can be omitted in the brand representation method. Different grades of Q235A, Q235B, Q235C and q235d mainly represent different impact temperatures. A refers to no impact, B is above 20 degrees, C is above 0 degrees, D-20 degrees, and the difference between a and e refers to the difference in impact temperature in their performance. They are: Q235 grade A, which is not required for impact toughness test; Q235B is used for impact toughness test at normal temperature (20 ℃); Grade Q235C is used for 0 ℃ impact toughness test; Grade Q235D is used for – 20 ℃ impact toughness test. Charpy V-notch specimens are used for impact toughness test. The impact toughness index is Akv. Akv ≥ 27j is required for the above grade B, C and D steels under different temperature requirements. At different impact temperature, the impact value is different.