Metal Manufacturing

Terminology

Primary Metal: A singular metal created after the ore is refined. Primary metals are used in forms such as ingots, sheets, etc.

Production Types

Wrought

"Wrought," as far as metals go, is defined as, "beaten out or shaped by hammering."

Cast

"Casting" as far as metals go, is described as, "casting involves pouring liquid metal into a mold, which contains a hollow cavity of the desired shape, and then allowing it to cool and solidify."

Aluminum

• Bauxite is the primary source of aluminum ore and is composed mostly of the following three aluminum-containing minerals:
  • Gibbsite→ Al(OH)₃ (Aluminum Hydroxide)
  • Boehmite → AlOOH (Aluminum Oxide Hydroxide)
  • Diaspore → AlOOH (Aluminum Oxide Hydroxide), with these last two dimorphous of one another.

• Bayer Process → Conversion of bauxite (aluminum ore) to aluminum oxide (Al₂O₃)
  • Bauxite + NaOH → Sodium Aluminate (Na[AlO₂]) → Aluminum Hydroxide (Al(OH)₃) + Heat → Aluminum Oxide (Al₂O₃)
  • Byproducts of the Bayer Process include:
    • Silica
    • Bauxite tailings → iron oxides, silica, calcia, titania, some unreacted alumina (aluminum oxide)
    • A portion of the aluminum hydroxide is used in other manufacturing processes