A668 Heat Treatment
| Class | Heat Treatment |
|---|---|
| A | Untreated |
| B | Annealed, or normalized, or normalized and tempered |
| C | Annealed, or normalized, or normalized and tempered |
| D | Annealed, or normalized, or normalized and tempered |
| E | Normalized and tempered or double normalized and tempered |
| F | Quenched and tempered, or normalized, quenched and tempered |
| G | Annealed, or normalized, or normalized and tempered |
| H | Normalized and tempered |
| J | Normalized and tempered, or normalized, quenched and tempered |
| K | Normalized, quenched and tempered |
| L | Normalized, quenched and tempered |
| M | Normalized, quenched and tempered |
| N | Normalized, quenched and tempered |
| Classes with an added ‘H’ are supplied on the basis of hardness values only. For example, AH. | |