Low Carbon AISI 1020 Carbon Steel

Product Overview

AISI 1020 Carbon Steel (also known as JIS S20C, DIN C22 1.0402, and BS 070M20) is a premium low-carbon structural steel compliant with EN 10083-2 and EN 10250-2 standards. Renowned for its exceptional versatility, this steel grade bridges global standards—with direct equivalents including China's 20# (GB/T 699)—making it a go-to choice for cross-industry applications. Its carbon content ranges from 0.17% to 0.24%, striking an ideal balance between formability and mechanical performance for lightly stressed to moderately demanding components. Whether supplied in untreated or normalized condition, DIN C22 1.0402 Steel delivers consistent ductility and toughness, with the option to enhance strength via case hardening or surface hardening processes.

Key Product Features

Superior Machinability & Weldability

BS 070M20 Steel boasts excellent machinability, allowing for smooth cutting, drilling, and shaping without excessive tool wear. Its carbon content below 0.25% ensures outstanding weldability—eliminating the need for pre-weld heating in most cases and producing strong, crack-free joints.

Flexible Heat Treatment Potential

While naturally ductile, JIS S20C Steel responds effectively to heat treatment. Case hardening or surface hardening elevates its surface hardness, expanding its use to components requiring enhanced wear resistance without sacrificing core toughness.

Wide Supply Range & Dimensional Precision

Available in cold-drawn bars (Φ3-Φ80mm), hot-rolled bars (Φ16-Φ300mm), hot-forged bars (Φ100-Φ1200mm), and plates (T:3-200mm), this steel adapts to diverse manufacturing needs. Surface finishes like grinding (tolerance +0/+0.05mm) and peeling ensure dimensional accuracy for precision applications.

Design & Material Specifications

1: Steel equivalent

Country	USA	Europe	China	British	Japan
Standard	ASTM A29	EN10083-2	GB/T699	BS970	JIS G4051
Grade	1020	C22/1.0402	20#	070M20/EN3B	S20C

2: Chemical composition

Grade	C	Si	Mn	P	S	Cr	Mo	Ni
1020	0.18-0.23	/	0.30-0.60	0.040Max	0.050Max	/	/	/
C22E/1.1151	0.17-0.24	0.40Max	0.40-0.70	0.030Max	0.035Max	0.40Max	0.10Max	0.40Max
20#	0.17-0.23	0.17-0.37	0.35-0.65	0.035Max	0.035Max	0.25Max	/	0.30Max
070M20	0.16-0.24	0.10-0.40	0.50-0.90	0.050Max	0.050Max	/	/	/
S20C	0.18-0.23	0.15-0.35	0.30-0.60	0.030Max	0.035Max	0.20Max	/	/

3: Mechanical properties

Mechanical properties for C22 quenching and tempering carbon steel according to EN10083-2.

Size range	Tensile strength	Yield strength	Alongation	Area of reduction	Impact value At RT/J
d≤16 t≤8	500-650Mpa	340Mpa Min	20% Min	50% Min	/
16＜d≤40 8＜t≤20	470-620Mpa	290Mpa Min	22% Min	50%Min	50J Min
40＜d≤100 20＜t≤60	630-780Mpa	370Mpa Min	17% Min	45%Min	/

Mechanical properties for C22 normalizing carbon steel according to EN10083-2 and ISO683-1.

Size range	Tensile strength	Yield strength	Alongation	Area of reduction	Impact value At RT/J
d≤16 t≤16	620Mpa	340Mpa Min	14% Min	/	/
16＜d≤100 16＜t≤100	580Mpa	305Mpa Min	16% Min	/	/
100＜d≤250 100＜t≤250	560Mpa	275Mpa Min	16% Min	/	/

Sampling and preparation of test pieces for C22 quenching and tempering steel.

1): According to EN10083-1, all samples shall be taken at a distance of 12.5mm below the heat treated surface

2): As stipulated in the contract between buyer and seller.

Mechanical properties for C22 open die forgings steel in the normalized and normalized and tempered conditions according to EN10250-2.

Size range	Tensile strength	Yield strength	Alongation		Impact value at RT/J
			L	Tr	L	Tr
d≤100	410Mpa Min	210Mpa Min	25% Min	/	/	/

Remark: L= Longitudinal    Tr = Transverse

Sampling and preparation of test pieces for steel forging.

1: According to EN10250-1, all samples shall be taken at a distance of 4/T below the heat treated surface (with a minimum of 20mm and a maximum of 80mm), and t/2 from the end (where t is the equivalent thickness of the thickness of the ruling section of the forging at the time of heat treatment.

2: As stipulated in the contract between buyer and seller

4: Surface hardness and hardenability

Heat Treatment	Hardness
Flame or Induction hardening	50-55HRC
Treated to improve shearability (+S)	130-170HBW
Soft annealed (+A)	110-140HBW
Quenched and tempred (+QT)	HRC28-32(Common Range)

5: Supply size & Tolerance & Stock size

Product type	Size range	Length
Cold drawn bar	Φ3-Φ80mm	6000-9000mm
Hot rolled bar	Φ16-Φ300mm	6000-9000mm
Hot forged bar	Φ100-Φ1200mm	3000-5800mm
Hot rolled plate/sheet	T:3-200mm; W:1500-2500mm	2000-5800mm
Hot Forged block	T: 80-800mm; W: 100-2500mm	2000-5800mm

Surface Finish	Turned	Milled	Grinding(Best)	Polished(Best)	Peeled(Best)	Black Forged	Black Rolled
Tolerance	+0/+3mm	+0/+3mm	+0/+0.05mm	+0/+0.05mm	+0/+0.1mm	+0/+5mm	+0/+1mm
Straighness	1mm/1000mm max.					3mm/1000mm max.

Qilu steel stock hot rolled bar and forged bars more than ten thousands tons every month, below our our stock size.

1): Stock diameter for hot rolled bar

20	22	25	28	30	32	35	38	40	42	45	48	50	55	60
65	70	75	80	85	90	95	100	105	110	115	120	125	130	140
150	160	170	180	190	200	210	220	230	240	250	260	270	280	290
300

Since the stocks change everyday, if you want to know our stock available information, please contact our salesman.

6：Forging processing

Put the C22 ingot into the furnace and heat to 1150-1200℃

Forge the ingot, forging temperature should be not less than 800-850℃

Cooling in the air after forged

7: Heat treatment

Soft annealed:

Heat C22 steel to 680-720℃ in the furnace

Soak at this temperature in the furnace

Cooling in the furnace

Normalized:

Heat C22 steel to 880-920℃ in the furnace

Soak at this temperature in the furnace

Cooling in the air

Quenching and tempering:

Heat C22 steel to 860-900℃ in the furnace

Soak at this temperature in the furnace

Quench in water

Temper steel at 550-660℃ in the furnace

Take out of C22 steel from furnace and cool in the air.

Remark: The conditions given above are for guidance, at the temperatures at the lower end of the range are generally applicable to hardening in water and those at the upper end for hardening in oil.

8: Weldability

C22 steel has good weldability. For steel materials, weldability has a strong relationship with the carbon content. When the carbon content is less than 0.25%, the weldability is generally good. The carbon content of C22 steel is around 0.17%-0.24%, which is below this threshold, so the weldability is excellent.

Application Scenarios

Mechanical Manufacturing

Shafts: Drive shafts, connecting rods, and lightly loaded rotating components

Fasteners: General-purpose bolts, nuts, and washers (leveraging weldability and formability)

Gears & Racks: Low-speed, low-load gears for light machinery

Automotive Industry

Chassis parts: Brackets, supports, and body structural components

Connecting parts: Pins, bushings, and non-critical fasteners

Construction & Infrastructure

Steel structural parts: Bridges, frames, and support brackets

Fasteners: Connection bolts for building structures (reliable and cost-effective)

Pipes & Containers

Low-pressure fluid pipes: Water and gas transportation

Storage tanks: For non-corrosive liquids and gases (utilizing ductility and weldability)

FAQ

What are the global equivalents of AISI 1020 Steel?

AISI 1020 corresponds to JIS S20C (JIS G4051), DIN C22 1.0402 (EN 10083-2), BS 070M20 (BS 970), and China’s 20# (GB/T 699).

Can AISI 1020 Steel be heat-treated for higher strength?

Yes—case hardening or surface hardening processes significantly improve surface strength and wear resistance, while retaining core ductility.

Is JIS S20C Steel suitable for welding?

Absolutely. Its carbon content (≤0.24%) ensures excellent weldability, with no pre-heat required for most thicknesses.

What supply forms are available for DIN C22 1.0402 Steel?

Options include cold-drawn bars, hot-rolled bars, hot-forged bars, hot-rolled plates, and hot-forged blocks—covering diameters from Φ3mm to Φ1200mm and thicknesses from 3mm to 800mm.