CSN 14221 Alloy Steel Bar 14221 Round Bars 14221 Rods

Product Description

CSN 14221 is a low-alloyed chromium-manganese steel from the Czech standard (ÄŒSN), specifically designed for case-hardening (carburizing). It is highly regarded for its ability to develop a very hard, wear-resistant surface while maintaining a tough, shock-resistant core.

1. Chemical Composition

The alloy is balanced to provide deep hardenability and excellent toughness after heat treatment.

2. Mechanical Properties (After Hardening)

The final properties depend heavily on the carburizing depth and the quenching media used (usually oil).

• Tensile Strength ($R_m$): 785 – 1080 MPa

• Yield Strength ($R_e$): $\ge$ 585 MPa

• Elongation ($A_5$): $\ge$ 10%

• Impact Toughness (KCU): $\ge$ 59 $J/cm^2$

• Core Hardness: Typically 30–40 HRC after quenching.

• Surface Hardness: Can reach 58–62 HRC after carburizing and hardening.

3. Key Technical Characteristics

• Case Hardening: This is the primary purpose of 14221. It absorbs carbon into the outer layer (0.5mm to 1.5mm deep), which is then hardened by quenching.

• Weldability: Good, but primarily in the delivery (annealed) state. Welding is not recommended after the case-hardening process as it will destroy the surface hardness and may lead to cracking.

• Forgeability: Excellent. It is easily hot-formed into complex shapes.

• Machinability: Good in the softened or normalized state, making it efficient for high-volume production of gears and shafts.

4. Global Equivalents

CSN 14221 is almost identical to the popular European grade 16MnCr5.

5. Common Applications

CSN 14221 round bars are the "go-to" choice for components subjected to high friction and medium-to-high core loads:

• Gears & Pinions: For transmissions and industrial gearboxes.

• Shafts: Spline shafts, camshafts, and drive shafts.

• Bushings & Pins: Piston pins and heavy-duty mechanical pivots.

• Joints: Universal joints and steering knuckles.

Stock Conditions

• Standard Rounds: Available from 5mm up to 500mm.

• Tolerances: Usually supplied as hot-rolled (h11/h12) or bright-drawn (h9) for precision CNC work.

• Heat Treatment State: Usually delivered in a Normalized or Soft Annealed (+A) condition to facilitate easier machining before final hardening.