Carbon Steel: Properties, Production, Examples and Applications
Carbon steel is an iron-carbon alloy, which contains up to 2.1 wt.% carbon. For carbon steels, there is no minimum specified content of other alloying elements, however, they often contain manganese. The maximum manganese, silicon and copper content should be less than 1.65 wt.%, 0.6 wt.% and 0.6 wt.%, respectively.
Types of carbon steel and their properties
Carbon steel can be classified into three categories according to its carbon content: low-carbon steel (or mild-carbon steel), medium-carbon steel and high-carbon steel . Their carbon content, microstructure and properties compare as follows:
| Carbon content (wt.%) | Microstructure | Properties | Examples |
|
| Low-carbon steel | < 0.25 | Ferrite, pearlite | Low hardness and cost. High ductility, toughness, machinability and weldability | AISI 304, ASTM A815, AISI 316L |
| Medium-carbon steel | 0.25 – 0.60 | Martensite | Low hardenability, medium strength, ductility and toughness | AISI 409, ASTM A29, SCM435 |
| High-carbon steel | 0.60 – 1.25 | Pearlite | High hardness, strength, low ductility | AISI 440C, EN 10088-3 |
Carbon Steel Description
Grade:
1)GB: Q195, Q215, Q235A, Q235B, Q235C, Q235D, Q255A, 255B, Q275, Q295A, Q295B, Q345B, Q345C, Q345D, Q345E, Q390A, Q390B, Q390C,Q390D, Q390E, Q420, Q420B, Q420C, Q420D, Q420E, Q460D, Q460E, Q500D, Q500E, Q550D, Q550E, Q620D, Q620E, Q690D, Q690E
2)EN: S185,S235JR, S275JR, S355JR, S420NL, S460NL S500Q, S550Q, S620Q, S690Q
3)ASTM: Grade B, Grade C, Grade D, A36, Grade 36, Grade 40, Grade42, Grade 50, Grade 55, Grade 60, Grade 65, Grade 80
4)JIS: SS330, SPHC, SS400, SPFC, SPHD, SPHE
PRODUCT DETAILS
| 1018 Cold Rolled Steel Coil |
| 1018 cold rolled steel coil is made of a general-purpose, low-carbon steel with good case hardening qualities. It is especially suited to cold forming and bending operations. 1018 steel is suitable for parts that require cold forming such as crimping, swaging, or bending. 1018 steel is mild steel with medium-low carbon content. AISI 1018 carbon steel is a free machining grade that is the most commonly available grade around the world. Although its mechanical properties are not very unique, it still can be easily formed, machined, welded and fabricated. |
| Product
Parameters |
| Product Name | 1018
Cold Rolled Steel Coil |
| Production
Process | Hot Rolling,
Cold Rolling |
| Material
Standards | AISI, ASTM,
ASME, DIN, BS, EN, ISO, JIS, GOST, SAE, etc. |
| Width | 100mm-3000mm |
| Length | 1m-12m, or
Customized Size |
| Thickness | 0.1mm-400mm |
| Delivery
Conditions | Rolling,
Annealing, Quenching, Tempered or Standard |
| Surface
Process | Ordinary, Wire
Drawing, Laminated Film |
| Chemical
Composition |
| Element | Content (%) |
| Manganese,
Mn | 0.60-0.90 |
| Carbon, C | 0.15-0.20 |
| Sulfur, S | 0.05
(max) |
| Phosphorous, P | 0.04
(max) |
| Iron, Fe | Balance |
| Mechanical
Properties |
| Properties | Metric | Imperial |
| Tensile
strength | 440 MPa | 63800 psi |
| Yield strength | 370
MPa | 53700
psi |
| Modulus of elasticity | 205
GPa | 29700
ksi |
| Shear modulus (typical for steel) | 80
GPa | 11600
ksi |
| Poisson’s ratio | 0.29 | 0.29 |
| Elongation at break (in 50 mm) | 15% | 15% |
| Hardness, Brinell | 126 | 126 |
| Hardness, Knoop (converted from Brinell hardness) | 145 | 145 |
| Hardness, Rockwell B (converted from Brinell hardness) | 71 | 71 |
| Hardness, Vickers (converted from Brinell hardness) | 131 | 131 |
| Machinability (based on AISI 1212 steel. as 100 machinability) | 70 | 70 |
| Scope of
Application |
| AISI
1018 carbon steel is commonly used in high volume screw machine parts
applications. The other applications of this alloy are as follows: |
| ● Shafts |
| ●
Spindles |
| ● Pins |
| ● Rods |
| ●
Sprocket assemblies. |