ferrocal

例句：

1. 1. The iron object has begun to ferrocal.
   这个铁制物体已经开始生锈了。
2. 2. The rust on the metal surface is visible under the microscope.
   金属表面的锈在显微镜下可见。
3. 3. The chemical reaction between iron and oxygen causes rust to form.
   铁与氧的化学反应导致生锈形成。