| 148 / | HD | METAL TREATMENT |
| 95 | DF | PROCESS OF MODIFYING OR MAINTAINING INTERNAL PHYSICAL STRUCTURE (I.E., MICROSTRUCTURE) OR CHEMICAL PROPERTIES OF METAL, PROCESS OF REACTIVE COATING OF METAL AND PROCESS OF CHEMICAL-HEAT REMOVING (E.G., FLAME-CUTTING, ETC.) OR BURNING OF METAL {17} |
| 538 | DF | .~ With casting or solidifying from melt {6} |
| 540 | DF | .~.~ Iron(Fe) or iron base alloy {5} |
| 543 | | .~.~.~ Containing at least 1.5 percent carbon {2} |
| 544 | DF | .~.~.~.~> With working |
| 545 | DF | .~.~.~.~> With tempering, ageing, solution treating (i.e., for hardening), precipitation hardening or strengthening, or quenching |