Carbon Steel / MED-C
Medium Carbon Steels (Engineering Steels)
Medium carbon engineering steels offering high strength, heat treatment capability, and excellent machinability. Preferred for precision machine parts, gears, shafts, and forging applications.
Technical Specifications
Key Features
- High tensile and yield strength
- Heat treatable (quenching + tempering)
- Induction surface hardening capability
- Excellent machinability
- Available in 3 forms (round, hex, square)
- Precision tolerance and surface via cold drawing
- Consistent metallurgical structure
- High plasticity suitable for forging
Applications
- Gears and gearbox components
- Shafts and axles
- Crankshafts and camshafts
- Engine and transmission parts
- High strength class bolts and nuts
- Precision machine shafts and pins
- Forged parts and die components
- Hydraulic cylinder rods
Dimension Table
| Form | Diameter/AF (mm) | Tolerance | Standard Length (m) | Surface Finish |
|---|---|---|---|---|
| Round | 4 - 20 | h9 | 3 (max 6) | Ra 0.8 - 1.6 |
| Round | 20 - 50 | h9 / h10 | 3 (max 6) | Ra 0.8 - 1.6 |
| Round | 50 - 100 | h10 / h11 | 3 (max 6) | Ra 1.6 - 3.2 |
| Hexagon | 6 - 30 | h9 | 3 (max 6) | Ra 0.8 - 1.6 |
| Hexagon | 30 - 60 | h10 / h11 | 3 (max 6) | Ra 1.6 - 3.2 |
| Square | 6 - 30 | h9 | 3 (max 6) | Ra 0.8 - 1.6 |
| Square | 30 - 60 | h10 / h11 | 3 (max 6) | Ra 1.6 - 3.2 |
Technical Notes
- 01Carbon content ranges between 0.32% - 0.50%.
- 02CK45 is the most widely used engineering steel (DIN equivalent: 1.1191).
- 03C35 is ideal for applications requiring medium strength and good machinability.
- 04Tensile strength of 600-900 N/mm2 achievable via quenching + tempering.
- 05Surface hardness of 50-58 HRC achievable via induction hardening.
- 06Pre-heating to 150-300°C recommended before welding; stress relief annealing required after welding.
- 07Standard length is 3 meters, available up to 6 meters on request.
Other Types
What is carbon steel?
Carbon steel is steel whose main alloying element is carbon (other elements at residual levels). It is classified by carbon content: low carbon (<0.25% C — formable, weldable), medium carbon (0.25–0.60% C — e.g. C45/1045, a strength/toughness balance) and high carbon (>0.60% C — springs and tools). It is the largest and most economical group of steels.
How carbon content sets the properties
As carbon rises, hardness and tensile strength increase while ductility, toughness and weldability fall. Low-carbon grades (C22, S235) serve deep drawing and welded fabrication; medium-carbon grades (C35–C60, EN 10083-2) are quenched and tempered for shafts, axles and gears; high-carbon grades go into springs, blades and wear parts. C45 is the most common medium-carbon grade: delivered normalized or Q&T, equivalent to AISI 1045. Because hardenability is limited, alloyed Q&T steels (42CrMo4) are preferred for large sections.
Frequently Asked Questions
What is C45 steel and where is it used?+
A medium-carbon Q&T steel with 0.42–0.50% C (equivalent to AISI 1045). The most common grade for shafts, axles, gear blanks and general machine parts.
Low vs medium vs high carbon steel?+
<0.25% C is low (weldable, formable), 0.25–0.60% is medium (heat-treatable, strong), >0.60% is high (very hard; springs/tools).
Can carbon steel be welded?+
Low-carbon grades weld easily. Medium-carbon may need preheat; high-carbon requires special procedures due to cracking risk.
Carbon steel vs alloy steel — what is the difference?+
In carbon steel, properties are set by carbon; in alloy steel, elements like Cr, Mo and Ni add hardenability, toughness and temperature resistance (e.g. 42CrMo4).
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