Aluminium Killed Steel

Definition: Aluminium Killed Steel that has been "quieted" by adding aluminium to remove trapped oxygen.

• The Problem: Dissolved oxygen creates gas bubbles (blowholes) during cooling.

• The Solution: Aluminium reacts with oxygen (2Al + 3O => Al2O3) to stop the bubbling.

• Benefits:

  - Uniformity: No bubbles means a consistent metal structure.

  - Toughness: Creates a fine grain structure that makes the steel stronger.

  - Shaping: It is the "gold standard" for pipes that need to be bent or stretched (deep drawing).