According to the GB/T16475-1996 standard, the basic status code is represented by an English capital letter. The subdivision status code is represented by the basic status code followed by one or more Arabic digits.
The basic status code is divided into the following 5 types:
|
Code |
Designation |
Description and application |
| F |
Free working state |
It is suitable for products that have no special requirements for work hardening and heat treatment conditions during the forming process, and the mechanical properties of the products in this state are not specified. |
| O |
Annealed condition |
Suitable for fully annealed products with the lowest strength |
| H |
Work hardening condition |
Suitable for products with increased strength through work hardening, after work hardening Additional heat treatment to reduce strength may or may not be performed. The H must be followed by two or three Arabic numerals. |
| W |
Solution heat treatment state |
An unstable state, only applicable to the natural aging of alloys at room temperature after solution heat treatment, the state code only indicates that the product is in the natural aging stage. |
| T |
Heat treatment condition (Different from F, O, H states) |
It is suitable for products that reach a stable state after heat treatment after work hardening (or not). |