Alloys of the 200 series contain copper as the principal alloying element, and are particularly useful for elevated temperature applications.
A201.0 is a high-strength, heat-treatable Al-Cu-Ag casting alloy. In the T7 (overaged) temper, it possesses high strength, moderate ductility and optimum resistance to stress-corrosion cracking. Refer to Section 3.1.3.4 for comments regarding the weldability of the alloy.
A material specification covering this alloy is presented in Table 3.8.1.0(a). Room-temperature mechanical and physical properties are presented in Table 3.8.1.0(b). The effect of temperature on thermal expansion is shown in Figure 3.8.1.0.
| Specification | Form |
|---|---|
| AMS-A-21180 | Casting (T7 temper) |
The temper index for A201.0 is: Section 3.8.1.1 covers the T7 temper.
| Specification | AMS-A-21180 | |||
|---|---|---|---|---|
| Form | Casting | |||
| Temper | T7 | |||
| Location Within Casting | Designated area | Nondesignated area | ||
| Strength Class Numbera | 1 | 2 | 10 | 11 |
| Basis | S | S | S | S |
| Mechanical Propertiesb,c: | ||||
| Ftu, ksi | 60 | 60 | 60 | 56 |
| Fty, ksi | 50 | 50 | 50 | 48 |
| Fcy, ksi | 51 | 51 | 51 | 49 |
| Fsu, ksi | 36 | 36 | 36 | 34 |
| Fbrud, ksi: | ||||
| (e/D = 1.5) | 95 | 95 | 95 | 88 |
| (e/D = 2.0) | 122 | 122 | 122 | 114 |
| Fbryd, ksi: | ||||
| (e/D = 1.5) | 74 | 74 | 74 | 71 |
| (e/D = 2.0) | 87 | 87 | 87 | 83 |
| e, percent | 3 | 5 | 3 | 1.5 |
| E, 103 ksi | 10.3 | |||
| Ec, 103 ksi | 10.7 | |||
| G, 103 ksi | 4.0 | |||
| μ | 0.33 | |||
| Physical Properties: | ||||
| ω, lb/in.3 | 0.101 | |||
| C, Btu/(lb)(°F) | 0.22 (at 212°F) | |||
| K, Btu/[(hr)(ft2)(°F)/ft] | 70 (at 77°F) | |||
| α, 10-6 in./in./°F | See Figure 3.8.1.0 | |||
| a The attainable strength class number is dependent on the casting configuration, complexity, and size (both weight and wall thickness). Favorable experience with a particular configuration may allow some foundries to produce a higher strength class number than others. In case of doubt regarding the strength class number, the designer should consult or negotiate with the foundry to determine the proper strength class number to assign for a specific casting. | ||||
| b For any casting process; i.e., special mold, permanent mold, or sand mold (including chilling). | ||||
| c The mechanical properties shown are reliably obtainable in castings of this alloy and heat-treat condition when produced under the quality assurance provisions of AMS-A-21180. These provisions require preproduction approval, documentation of foundry procedures, and specific destructive and nondestructive testing procedures for the acceptance of each production lot of castings. Strict adherence to these requirements is mandatory if these properties are to be reliably assured in each casting. | ||||
| d Bearing values are “dry pin” values per Section 1.4.7.1. | ||||
Figure 3.8.1.0. Effect of temperature on the thermal expansion of A201.0 aluminum alloy casting.
Figure 3.8.1.1.6 presents a typical tensile stress-strain curve. Strain-control fatigue data are shown in Figures 3.8.1.1.8(a) through (c).
Figure 3.8.1.1.6. Typical tensile stress-strain curve for A201.0-T7 aluminum alloy casting, designated area, at room temperature.
Figure 3.8.1.1.8(a). Best-fit strain-life (ε/N) curves, cyclic stress-strain curve, and mean stress relaxation curve for A201.0-T7 casting at 75°F.
Figure 3.8.1.1.8(b). Best-fit strain-life (ε/N) curves, cyclic stress-strain curve, and mean stress reduction curve for A201.0-T7 casting at 200°F.
Figure 3.8.1.1.8(c). Best-fit strain-life (ε/N) curves, cyclic stress-strain curve, and mean stress relaxation curve for A201.0-T7 casting at 350°F.