Q 275 Mild Steel Sheet

Q 275 Mild Steel Sheet

Q275 steel is a Chinese carbon structural steel, “Q” is the first letter of Chinese spelling of “qu fu dian”, the translation is “Yield Point” or “Yield Strength”, “275” is short for the unit value “275 MPa”, and the tensile strength is 410-540 MPa (N/mm2), all data are tested with 16mm diameter steel bars or 16mm thickness steel plates.

The latest executive standard of Q275 steel is GB/T 700-2006, and chemical composition and physical properties are equivalent to JIS standard SS490, ISO standard E275A, no equivalent to ASTM standard.

Q275 mild steel  plate has high strength, good plasticity and cutting performance, certain welding performance, small parts can be quenched and strengthened, and used for manufacturing parts with high strength, such as gears and shafts, sprocket, key, bolt, nut, steel for agricultural machinery, conveyor chain and chain link.

Q275 Steel Chemical Composition

Q275 Steel Mechanical Property

Steel Grade

Quality

Yield Strength (≥N/mm2)

Tensile Strength (N/mm2)

Elongation (≥%)

Impact Test (V notch)

Thickness or Dia. (d) mm

Thickness or Dia. (d) mm

Temp. ℃

Absorbed Energy (Vertical, ≥J)

d≤16

16< d ≤40

40< d ≤60

60< d ≤100

100< d ≤150

150< d ≤200

d≤40

40< d ≤60

60< d ≤100

100< d ≤150

150< d ≤200

Q275

Q275A

275

265

255

245

225

215

410-540

22

21

20

18

17

–

–

Q275B

20

27

Q275C

0

Q275D

-20

What is Ms Steel Sheet?

Steel is mostly composed of iron. Depending on different amounts of carbon content, there are low-Carbon Steel (also called mild steel or plain carbon steel), medium-carbon steel, and higher carbon steel.
The following chart shows the differences and characteristics of the three steel types:

	Carbon content (wt. %)	Microstructure	Characteristics	Examples
Low-carbon steel (Mild steel)	Less than 0.25	Pearlite, ferrite	Soft, cheap, very ductile, easy to machine and weld	AISI105, AISI 316L, Q195, Q215, Q235, 08F, 15Mn, 20Mn
Medium-carbon steel	0.25 to 0.60	Martensite	Reasonably ductile, hard, strong and not easy to harden	AISI 409, 45#, 40CR, 20CR, SCM 435
High-carbon steel (carbon tool steel)	0.60 to 1.25	Pearlite	Very hard, strong, unyielding, hard to machine and weld	T7, T7A, T8Mn, T8MnA, AISI440C

From the above chart, mild steel is a steel type that contains 0.05%-0.25% carbon. Due to its malleability and ductility, the material is easy to form and machine. Mild steel parts are generally very suitable for stamping, forging. Mild steel is widely used in tools, automotive body parts, construction, and infrastructure.

Mechanical Properties Of Mild Steel
As you could judge from the chart above, mild steel has lower carbon content than other carbon steel. The mild steel has a mere carbon content of 0.25%.

Mild steel has great impact strength, great ductility and weldability, good malleability with cold-forming possibilities. With these properties, CNC-machining mild steel is easier than CNC-machining other types of steel.

The major disadvantage of mild steel is that it has a relatively low tensile strength, which means it’ll break more easily than other types of steel.

Fortunately, a heat-treatment process called carburizing can be used to improve tensile strength. Carburizing is a surface-hardening process that heats the mild steel to a certain temperature then cools down the steel, which makes the steel hardened on the surface when keeping the core of the steel soft and ductile.