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Source: Aluminum Association [5].

Note: Density and specific gravity are dependent upon composition, and variations are discernible from one cast to another for most alloys. The nominal values shown below should not be specified as engineering requirements but are used in calculating typical values for weight per unit length, weight per unit area, covering area, etc. The density values are derived from the metric and subsequently rounded. These values are not to be converted to the metric. X.XXX0 and X.XXX5 density values and X.XX0 and X.XX5 specific gravity values are limited to 99.35 percent or higher purity aluminum.

Source: Aluminum Association [5].

Note: Density and specific gravity are dependent upon composition, and variations are discernible from one cast to another for most alloys. The nominal values shown below should not be specified as engineering requirements but are used in calculating typical values for weight per unit length, weight per unit area, covering area, etc. The density values are derived from the metric and subsequently rounded. These values are not to be converted to the metric. X.XXX0 and X.XXX5 density values and X.XX0 and X.XX5 specific gravity values are limited to 99.35 percent or higher purity aluminum.

1625 Btu ■ in./ft2 h°F(234 W/m ■ K) and an electrical conductivity of 62% of the International Annealed Copper Standard (IACS) at 68°F (20°C) for equal volume, or 204% of IACS for equal weight.

The coefficient of thermal expansion, the rate at which material expands as its temperature increases, is itself a function of temperature, being slightly higher at greater temperatures. Average values are used for a temperature range, usually from room temperature [68°F (20°C)] to water's boiling point [212°F (100°C)]. A commonly used number for this range is 13 x 10-6/°F(23 x 10-6/°C). This compares to 18 for copper, 15 for magnesium, 9.6 for stainless steel, and 6.5 x 10-6/°F for carbon steel.

For wrought alloys, typical physical properties are given in Table 9.12. Typical physical properties of cast alloys are given in Table 9.11.

9.2.2 Mechanical Properties

Mechanical properties are properties related to the behavior of material when subjected to force. Most are measured according to standard test methods provided by the American Society for Testing and Materials (ASTM). The mechanical properties of interest for aluminum and ASTM test methods by which they are measured given in Table 9.13.

Mechanical properties are a function of the alloy and temper as well as, in some cases, product form. For example, 6061-T6 extrusions have a minimum tensile ultimate strength of 38 ksi (260 MPa), while 6061-T6 sheet and plate have a minimum tensile ultimate strength of 42 ksi (290 MPa).

TABLE 9.11 Typical Physical Properties of Commonly Used Sand and Permanent Mold Casting Alloys

Alloy

Temper

Specific Gravity®

Density® (lb/in.3)

Approximate

Melting Range (°F)

Electrical Conductivity (% IACS)

Thermal Conductivity at 25°C, CGS®

Coeff. of Thermal Expansion, per °F x 10-6

68-212 °F

68-572 °F

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