Technical Overview
Case hardening is a critical metallurgical process used to increase the surface wear-resistance of steel components while maintaining a tough, ductile core. This process is essential for engineering parts subject to cyclic wear and heavy impact shock loading.
Metallurgical Principles
The process involves heating parts in a carbon-rich atmosphere (carburizing) so that carbon diffuses into the outer surface layers. The parts are then immediately quenched in oil to transform the high-carbon case into a hard martensitic structure. Subsequent tempering relieves residual quenching stresses and restores fracture toughness.
Typical Thermal Cycle Parameters
Typically heated in our pit-type Gas Carburizing Furnaces to 880-930?C. Soaking time depends on the target case depth. Quenched in circulating oil and tempered at 150-200?C.
Key Component Applications
Commonly specified for: Automotive transmission gears, pinions, crankshafts, kingpins, steering linkages, and heavy engineering bushings.
Process Specifications Table
| Parameter / Metric | Operational Specification Value |
|---|---|
| Furnace Compatibility | GCF-1, GCF-2, GCF-3 (Up to ?750 x 1400 mm loading size) |
| Hardness Target | 58 to 62 HRC (Case surface) |
| Case Depth Range | 0.3 mm up to 2.0 mm (according to customer draw-sheet) |
| Recommended Materials | Low-carbon alloy steel (e.g., 20MnCr5, EN353, EN354, 8620, SAE 1018) |