What did Surface Carburization look like?

The finished product has a hard, wear-resistant exterior (high-carbon steel layer) and a tough, flexible core (low-carbon wrought iron), forming a gradient material. Commonly used for sword edges and farm tools.

How did Surface Carburization work?

Wrought iron object buried in charcoal powder + bone meal carburizer → sealed and heated to 900-950°C for several hours → carbon atoms diffuse inward from the surface → surface carbon content rises to 0.8-1.0% → removed and quenched.

← DiscoveriesA-Tier · Major Innovation

表层渗碳技术

Surface Carburization

Solid carburization: wrapping wrought iron objects in charcoal and heating for extended periods, allowing carbon atoms to diffuse into the surface layer, hardening the exterior while preserving a tough interior.

表层渗碳

Scientific Principle

Fick's second law of diffusion: carbon concentration gradient drives carbon atom diffusion from the high-concentration surface into the interior. Diffusion depth ∝ √(Dt).

表层渗碳技术

Surface Carburization

Scientific Principle

Related · 汉代