This is the quality of metal that describes its ability to spring back after it is flexed. It doesn’t have anything to do with how hard the metal is.
} Soft temper means that when it is bent, it stays bent, and it doesn’t take much force to do it.
} Hard temper means that when it is bent, it springs back flat, and it takes a lot of force to put a kink into it.
The temper designation follows the alloy designation and shows the actual condition of the metal. (Alloy designation by a letter and dash).
As fabricated – Applies to products of a forming process in which no special control over thermal or strain hardening conditions is employed
Annealed – Applies to product which has been heated to produce the lowest strength condition to improve ductility and dimensional stability
Strain Hardened – Applies to products which are strengthened through cold-working. The strain hardening may be followed by supplementary thermal treatment, which produces some reduction in strength. The “H” is always followed by two or more digits
Solution Heat-Treated – An unstable temper applicable only to alloys which age spontaneously at room temperature after solution heat-treatment
Thermally Treated - To produce stable tempers other than F, O, or H. Applies to product which has been heat-treated, sometimes with supplementary strain-hardening, to produce a stable temper. The “T” is always followed by one or more digits
The first digit after the H indicates a basic operation:
H1 – Strain Hardened Only.
H2 – Strain Hardened and Partially Annealed.
H3 – Strain Hardened and Stabilized.
H4 – Strain Hardened and Lacquered or Painted.
The second digit after the H indicates the degree of strain hardening:
HX2 – Quarter Hard HX4 – Half Hard HX6 – Three-Quarters Hard
HX8 – Full Hard HX9 – Extra Hard
Solution Heat Treatments
Improve mechanical properties by developing maximum practical concentration of the hardening constituents in solid solution; involves heating to above the critical temperature, holding, and abrupt quenching.
Cooling alloy fast enough to retain a supersaturated solid solution of alloying constituents without introducing adverse metallurgical or mechanical conditions; Most common quenching media are water, air blast, soap solutions and hot oil
Sometimes called age hardening, used on aluminum, copper, nickel, magnesium and some stainless alloys
The ageing process can be divided into two main categories after the ageing temperature
The Heat treatable alloys changes properties when stored at room temperature after solution heat treatment and quenching.
Artificial Ageing: By heating the solution heat treated material to a temperature above room temperature and holding it there the precipitation accelerates and the strength is farther increased compare to natural ageing
Preheating or Homogenizing
Typically a preliminary to other treatments to reduce chemical segregation of cast structures and improve their workability; reduce brittleness in cast structure
Aids in workability by softening aluminum and heat treated alloy structures to relive stresses and stabilize properties and dimensions of product
This Data is indicative only and must not be seen as a substitute for the full specification from which it is drawn. In particular, the mechanical property requirements vary widely with temper, product and product dimensions. The information is based on our present knowledge and is given in good faith. However, no liability will be accepted by the Company is respect of any action taken by any third party in reliance thereon. As the products detailed may be used for a wide variety of purposes and as the Company has no control over their use; the Company specifically excludes all conditions or warranties expressed or implied by statute or otherwise as to dimensions, properties and/or fitness for any particular purpose.