q235 steel (q235a q235b q235c q235d)
q235 is ordinary carbon structural steel. q represents the yield limit of this material. the latter 235 refers to the yield value of this material, which is about 235mpa.
consists of q+number+quality grade symbol+deoxygenation method symbol. its steel number is prefixed with "q", which represents the yield point of the steel. the following number represents the value of the yield point, and the unit is mpa. for example, q235 represents a carbon structural steel with a yield stress (σs) of 235 mpa.
q235 quality grades are divided into a, b, c, d, e, followed by a grade with the poorer quality and d grade with the highest quality. q235a, q235b, q235c, and q235d represent different grades, mainly because the temperature of impact is different.
features and applications
1. it is widely used in construction and engineering structures. it is used to make steel bars or to build factory buildings, high-voltage power transmission towers, bridges, vehicles, boilers, containers, ships, etc., and it is also used as a large number of mechanical parts with low performance requirements. c and d grade steel can also be used as some professional steel.
2. it can be used for various mold handles and other unimportant mold parts.
3. q235 steel is used as the punch material. after quenching, it can be used directly without tempering. the hardness is 36~40hrc, which solves the phenomenon of the punch chipping during use.
specification
q235 material chemical composition based on heat analysis.
q235a grade contains c ≤0.22% mn≤1.4% si ≤0.35% s ≤0.050 p ≤0.045
q235b grade contains c≤0.20% mn≤1.4% si ≤0.35% s ≤0.045 p ≤0.045 (with the consent of the purchaser, the carbon content can be no more than 0.22%)
q235c grade contains c ≤0.17% mn≤1.4% si ≤0.35% s ≤0.040 p ≤0.040
q235d grade contains c ≤0.17% mn≤1.4% si ≤0.35% s ≤0.035 p ≤0.035
mechanical behavior
density: 7.85g/cm^3
elastic modulus (e/gpa): 200~210
poisson's ratio (ν): 0.25~0.33
tensile strength (σb/mpa): 370-500
yield strength (thickness or diameter less than or equal to 16mm): 235
material linear expansion coefficient α (1/°c): 1.20e-05
elongation (δ5/%):
≥26 (a≤16mm)
≥25 (a>16-40mm)
≥24 (a>40-60mm)
≥23 (a>60-100mm)
≥22 (a>100-150mm)
≥21 (a>150mm)
where a is the thickness or diameter of the steel.