Deformed Aluminum And Aluminum Alloy State, Code

The 1st digit after the H represents the basic handler for obtaining the state, as follows:
H1—Simple work hardening treatment state. It is suitable for the state where the required strength is obtained only by work hardening without additional heat treatment. H2—The state of work hardening and incomplete annealing. It is suitable for products whose strength is reduced to the specified index after incomplete annealing after the degree of work hardening exceeds the specified requirements of the finished product. For alloys that soften naturally at room temperature, H2 has the same minimum ultimate tensile strength value as the corresponding H3; for other alloys, H2 has the same minimum ultimate tensile strength value as the corresponding H1, but the elongation is slightly higher than H1 . H3—The state of work hardening and stabilization. It is suitable for products whose mechanical properties are stable after heat treatment after work hardening or due to heat during processing. The H3 temper is only suitable for alloys that gradually age soften (unless stabilized) at room temperature. H4—The state of work hardening and painting treatment. It is suitable for products which, after work hardening, have been lacquered resulting in incomplete annealing.​​

The second digit after H indicates the degree of work hardening of the product. The number 8 represents the hard state. The minimum tensile strength value of HX8 is usually specified by the sum of the minimum tensile strength in the O state and the strength difference specified in Table 2. For states between the O (annealed) and HX8 states, numbers from 1 to 7 should be added after the HX code to indicate, respectively, adding the number 9 after HX indicates a superhard state with a greater degree of work hardening than HX8, various HXX subdivision state code and corresponding work hardening degree: