AMS 2772
Heat Treatment of Aluminum Alloy Raw Materials
Heat treatment of wrought aluminum alloy raw material — sheet, plate, extrusions, bar, rod, wire, tubing and forgings — by the producer or reheat treater to the tempers called out in the material specifications.
What AMS 2772 specifies
AMS 2772 is the mill-level companion of AMS 2770: it controls how producers and reheat treaters solution treat, quench, stress relieve and age raw aluminum product so that it meets the temper properties in the AMS material specifications (for example AMS 4037 2024-T3 sheet, AMS 4045 7075-T6 sheet, AMS 4050 7050-T7451 plate). It shares AMS 2770's solution temperature tables, quench-delay limits and furnace uniformity requirements, and additionally defines the mechanical stress-relief steps that turn a T6 into T651 (stretching plate to 1.5–3 % permanent set) or T652 (compression), covers continuous heat-treat lines for sheet and extrusions, and sets the lot and sampling rules used for statistically based mechanical-property acceptance. Buyers rarely cite AMS 2772 on a drawing; the material specification invokes it automatically. It matters when raw stock is re-heat-treated or when a supplier's certification is being checked.
Tests and the drawing call-out
Tests the document imposes
- Tensile test per ASTM B557 by lot and thickness per the material specification
- Hardness and electrical conductivity screening (AMS 2658 practice) where permitted
- Stretch / compression permanent-set record for Tx51 / Tx52 tempers
- Exfoliation (ASTM G34) and stress-corrosion tests for 7000 series T7x tempers when the material specification requires them
- Furnace TUS / SAT per AMS 2750; quench delay records
How to cite it
Drawing call-out
MATERIAL: 7050-T7451 PLATE PER AMS 4050 (PRODUCER HEAT TREATMENT PER AMS 2772)Angle brackets mark the choices the drawing must make; every finish page shows a completed example.
Heat treatments specified to AMS 2772
| Treatment | Role | Cost |
|---|---|---|
Aluminum O-temper annealing removes strain hardening and produces the softest standard wrought condition. | Governing | $$ |
AMS 2772 — frequently asked
Do I need to cite AMS 2772 on my drawing?
No. Cite the material specification and temper (for example 7050-T7451 per AMS 4050); that specification invokes AMS 2772 for the producer. Cite AMS 2770 instead when your part will be heat treated after machining.
What does the "51" in T651 or T7351 mean?
Stress relieved by stretching: after the quench the plate or extrusion is pulled to about 1.5–3 % permanent set before ageing, which flattens the residual-stress profile so machined parts do not warp. T652 is stress relieved by compression (forgings); T654 by a combination of the two.
Can raw stock be re-heat-treated?
Yes, under AMS 2772 or AMS 2770 with the same limits on the number of re-solution treatments and on Alclad diffusion. Heavy plate re-treated by a job shop loses its stretch stress relief and may distort badly when machined, so re-treating T651 plate is usually a poor idea.
Why do 7000 series T7x tempers carry extra tests?
Because the overaged tempers exist for stress-corrosion and exfoliation resistance, the material specifications require conductivity limits and periodic exfoliation (ASTM G34 EXCO) or SCC tests as evidence that the two-stage age was completed; 7075-T73 material reading below 40 % IACS is rejected.
AMS 2772 is copyrighted by SAE International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗