| 420 / | HD | ALLOYS OR METALLIC COMPOSITIONS |
| 528 | DF | ALUMINUM BASE {7} |
| 542 | | .~ Magnesium containing {3} |
| 543 | DF | .~.~> Titanium, zirconium, hafnium, vanadium, niobium, or tantalum containing {2} |
| 546 | DF | .~.~> Silicon containing |
| 547 | DF | .~.~> Iron, cobalt, or nickel containing |