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 |
| Medium-carbon steel | 0.25 – 0.60 | Martensite | Low hardenability, medium strength, ductility and toughness |
| High-carbon steel | 0.60 – 1.25 | Pearlite | High hardness, strength, low ductility |
Carbon Steel DescriptionGrade: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, Q690E2)EN: S185,S235JR, S275JR, S355JR, S420NL, S460NL S500Q, S550Q, S620Q, S690Q3)ASTM: Grade B, Grade C, Grade D, A36, Grade 36, Grade 40, Grade42, Grade 50, Grade 55, Grade 60, Grade 65, Grade 804)JIS: SS330, SPHC, SS400, SPFC, SPHD, SPHEPRODUCT 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. |
