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 |