Co-fusion steel (guangang)
Acero por cofundición (guangang)
- Date
- c. 550 · confidence medium
- Place
- Jinyang (Taiyuan), Shanxi, China
- Credited to
- Qiwu Huaiwen (Northern Qi)
- Field
- Matter & energy
What it is
Cast iron is melted over wrought iron so that the carbon distributes between the two, producing steel of controlled carbon content. It was the standard Chinese method of making steel until the modern era.
It has been compared to the Siemens-Martin process (1860s), which also mixes cast and wrought iron.
What it led to
- steel production for swords and tools
- cheap steel without relying on slow forging