| 420 / | HD | ALLOYS OR METALLIC COMPOSITIONS |
| 8 | DF | FERROUS (I.E., IRON BASE) {24} |
| 34 | DF | .~ Nine percent or more chromium containing {14} |
| 67 | ![]() | .~.~ Molybdenum or tungsten containing {2} |
| 68 | DF | .~.~.~> Titanium, zirconium or hafnium containing |
| 69 | DF | .~.~.~> Vanadium, niobium or tantalum containing |