鋼鉄

1. Origins, structure, and basic meaning

• Structure: 鋼鉄 (こうてつ) is a noun for steel used in structures and manufactured objects.
• Basic usage: It describes strong steel in a bridge framework or heated steel being hammered into shape.
  • 橋の骨組みには丈夫な鋼鉄が使われている。 — Strong steel is used in the bridge framework.
  • 職人は熱した鋼鉄を何度も打って形を整えた。 — The artisan repeatedly hammered heated steel into shape.

2. Common pitfalls and similar expressions

• Material and processing
  • 鋼鉄 names the material and can be modified for its quality, as in 丈夫な鋼鉄, or its processing state, as in 熱した鋼鉄.