| 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} |
| 559 | DF | .~ Heating or cooling of solid metal {22} |
| 579 | DF | .~.~ Iron(Fe) or iron base alloy {24} |
| 646 | DF | .~.~.~ With restraining of metal from expanding or contracting during heating or cooling {1} |
| 647 | | .~.~.~.~ Die quenching |