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Q235 Steel Equivalent, Properties, Specification, Composition

Views: 27776 Author: Site Editor Publish Time: 2022-07-06 Origin: Site

Q235 Steel (Q235A Q235B Q235C Q235D)

Q235 steel is a plain carbon structural steel which is widely used in China, Q235 material in Chinese standard GB/T 700 is divided into 4 quality grades: Q235A, Q235B, Q235C and Q235D; Density of this steel is 7.85 g/cm3, tensile strength is 370-500 MPa; yield strength is 235 MPa (data are for steel bar or steel plate diameter ≤ 16mm). Since it’s mild steel, it is used directly without heat treatment.

Meaning and Designation

“Q” is the first letter of Chinese spelling of “Qu Fu Dian”, which means Yield Point.

“235” refers to the minimum yield strength 235 MPa tested with steel diameter ≤ 16mm.

Features and Applications

Q235 steel has good plasticity, toughness and weldability, as well as a certain strength, good cold bending performance. Q235 material is usually rolled into wire rod or round steel, square steel, flat steel, angle steel, I beam, channel steel, other sections and steel plates. These products are widely used in construction and engineering welded structures, to make steel bars or build factory buildings, high voltage transmission towers, bridges, vehicles, boilers, containers, etc., and also used as a mechanical part with less demanding performance such as less stressed rods, connecting rods, screws, nuts, ferrules, brackets, and stands, etc.

Q235 VS A36, S235

Data Sheet and Specification

The following tables show Q235A, Q235B, Q235C and Q235D steel datasheet and specification, including chemical composition, physical and mechanical properties, etc.

Q235A, Q235B, Q235C, Q235D Steel Chemical Composition

The table below lists Q235 material chemical composition based on heat analysis.

Chemical Composition (heat analysis), %, ≤
Steel Grade	Quality Grade	C	Si	Mn	P	S	Deoxidation Method
Q235	Q235A	0.22	0.35	1.40	0.045	0.050	Rimmed / Killed
	Q235B	0.20	0.35	1.40	0.045	0.045	Rimmed / Killed
	Q235C	0.17	0.35	1.40	0.040	0.040	Killed
	Q235D	0.17	0.35	1.40	0.035	0.035	Exceptionally Killed

Q235 Steel Properties

The following list summarizes Q235 steel properties including physical and mechanical properties.

Physical Properties

Notes:

10-6·K-1 = 10-6/K
1 Ω·mm²/m = 1 μΩ·m
1 g/cm3 = 1 kg/dm3 = 1000 kg/m3
1 GPa = 1 kN/mm2
1 MPa = 1 N/mm2

Physical Properties
Density, g/cm3	7.85
Melting point, ℃	about 1493
Specific heat capacity, J/(Kg·K)	470 at 20 ℃
Electrical resistivity, μΩ·m	about 0,15 (20 ℃)
Elastic modulus, GPa (kN/mm2)	200
Thermal conductivity, (W/m·K)	53-49 (0-100 ℃)
Coefficient of thermal expansion, (10-6/K)	11.3-11.6 (20 ℃)
Young’s modulus, GPa (kN/mm2)	200
Poisson’s ratio	0.24-0.28

Mechanical Properties

Yield strength and tensile strength are listed in the table below.

1 MPa = 1 N/mm2

		Yield Strength (MPa, ≥); Thickness or Dia. (d) mm					Tensile Strength (MPa)
Steel Grade	Quality	d≤16	16< d ≤40	40< d ≤100	100< d ≤150	150< d ≤200	d≤100
Q235	Q235A	235	225	215	195	185	370-500
	Q235B
	Q235C
	Q235D

Minimum Elongation

	Elongation (≥ %); Thickness or Dia. (d) mm
Steel Grade	d≤40	40< d ≤60	60< d ≤100	100< d ≤150	150< d ≤200
Q235	26	25	24	22	21

Minimum Charpy Impact

		Charpy impact (V notch)
Steel Grade	Quality	Temp. ℃	Impact energy (longitudinal, ≥ J)
Q235	Q235A	–	–
	Q235B	+20	27
	Q235C	0
	Q235D	-20

Bending Test Results of Q235 Material

Cold Bending Test 180° (B=2a)
Grade	Sample Orientation	Steel Dia. (d) of Curve Center
		d≤ 60mm	60
Q235	Vertical	a	2a
	Horizontal	1.5a	2.5a

B= Sample Steel Width; a= Sample Diameter or Thickness.

Steel rolled with Q195 and Q235B grade rimmed steel, the thickness or diameter of which is not more than 25mm.