GB/T700 Q235B Mild steel plate,Carbon steel coil
GB/T700 Q235B is the most common used among carbon steel.It is equal to steel grades ASTM A36,JIS G3101 SS400,EN 10025-2 S235JR.BBN steel stocks carbon steel Q235B in coils shape and plate shape at port warehouses with many sizes.
Technical Requirements & Additional Services:
♦ Low temperature impacting test
♦ Cutting and welding as per end user's demands
♦ More striction on some chemical elements contains
♦ Issued Orginal Mill test certificate under EN 10204 FORMAT 3.1/3.2
♦ Ultrasonic test under GB/T2970,JB4730,EN 10160,ASTM A435,A577,A578
Mechnical property for GB/T700 Q235B Carbon steel:

Thickness (mm)
Q235B ≤ 16 > 16 ≤ 40 > 40 ≤ 60 > 60 ≤ 100 > 100 ≤ 150 > 150
Yield strength (≥Mpa) 235 225 215 215 195 185
Tensile strength (Mpa) 370-500

Chemical composition for GB/T700 Q235B Carbon steel (Heat Analysis Max%):

Main chemical elements composition of Q235B
C Si Mn P S
0.20 0.35 1.40 0.045 0.045

Comparison of A36, SS400 and Q235 plate:
As can be seen from data above, ASME standard A36 and China standard Q235 materials are named according to yield strength of material, and for SS400 is tensile strength. From the analysis of mechanical properties, A36 and SS400 are more equivalent, while Q235 material is less.
Substitution of A36, SS400 and Q235 steel plate
Although the Q235 steel grade steel plate has lower mechanical properties than A36 and SS400 material, but in actual operation process, as long as the buyers do not have special requirement, often these three kinds of materials can be substituted. If only from mechanical properties of materials, it is acknowledged that mechanical properties of A36 and SS400 are similar to those of high quality carbon structural steel 20#. Tensile strength of 20# steel is not less than 410; yield strength is not less than 245; mechanical properties of SS400 and A36 are about the same.
Different standard formulation parties:
A36 for American Standard ASME standard (ASTM specification equivalent) materials, SS400, Standard JIS G3101 (common structure with rolling steel) materials, Q235 GB700 standards GB material. GB700:Q235 G3101:SS400 JIS ASME:A36
Different chemical composition:
The content of Mn element in A36 due to the plate thickness (or diameter) of different instead, below 20mm, without Mn. Q235 of C, Si, Mn, S, P and other elements of the content have made a request, but SS400 as long as the S, P is less than 0.050, the other did not make a request.
Different mechanical property:
The tensile strength of A36 is Ksi 58~80 (about 400~550MPa), the yield strength is 36 Ksi (about 250MPa); the tensile strength of 370~500 is MPa Q235, and the yield strength is 235MPa; The tensile strength of 400~510 is MPa SS400, and the yield strength is 245MP (SS400 and Q235's mechanical properties are all in the case of steel plate thickness less than 16mm).