Aluminum (Al)
- Practical Electron Microscopy and Database -
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Table 2025a. Properties of aluminum (Al).

Resistivity (10-6 Ω•cm) Corrosion in air Melting point (°C) 2.66 Good 660 Specific heat capacity (Jkg-1K-1) 917 2.358 Heat conductivity (kh,Wcm-1K-1) 2.22 395 Vaporization heat (Qv, J-g-1) 10470 Good Vaporization temperature (Tv, °C) 2450 2.1 Youngs modulus (10-11 dyn cm-2) 7.06 23.5 Work Function (eV) 4.28 1.61 Absorption (1-R) 0.10 for 1 µm light 2.7 4.048 ~ 4.050

Table 2025b. Lattice Spacing of aluminum (Al).

Miller Indices hk1
Lattice Spacing (d, Å)
111 2.338
200 2.024
220 1.431
311 1.221
222 1.1690
400 1.0124
331 0.9289
420 0..9055
422 0.8266

Figure 2025a shows the atomic structure of Al.

Figure 2025a. Atomic structure of Al.

The growth rate of pure aluminum (Al) bulk follows an empirical equation given by, [1]

------------------------------- [2025a]

where,
n -- The time exponent,
D -- The mean grain diameter,
t -- The time of annealing,
K -- The temperature-dependent constant given by,

------------------------------- [2025b]

where,
Q -- The activation energy for grain growth,
K0 -- A constant,
R -- The universal gas constant,
T -- The absolute temperature.

Table 2025c lists the different grain growth rates of pure bulk Al and Al-4% Cu alloy thin films after 100 min annealing. The grain growth rate increased by one order of magnitude in pure bulk Al, while in the same temperature range the growth rate only increased by a factor of about 0.8 in the Al-4% Cu alloy thin films. Moreover, the growth rates for pure Al are ~103 times greater than those for the Al-4% Cu alloy films.

Table 2025c. Grain growth rates of pure bulk Al and Al-4% Cu alloy thin films after 100 min annealing.

Temperature (°C) Rate (Å/min)
Pure bulk Al [1] Al - 4% Cu films [2]
400 1.0 × 103 1.8
450 3.9 x 103 2.4
500 1.3 × 104 3.2

Figure 2025b shows the solid solubility of some impurities (including Al) in silicon.

Figure 2025b. Solid solubility of impurities in silicon.

As listed in Table 2025d, substances with large bonding energies usually have high melting temperatures.

Table 2025d. Bonding energies and melting temperatures of metallic substances.

Bonding type

Substance
Bonding energy
Melting point (°C)
kJ/mol kcal/mol eV/Atom, Ion, or Molecule
Metallic
Typical value 50-1000
Hg 68 16 0.7 -39
Al 324 77 3.4 660
Fe 406 97 4.2 1538
W 849 203 8.8 3410

Figure 2025c shows the solubility for impurities (including Al) in SiC.

Figure 2025c. Solubility for impurities in SiC.

Table 2025e. Some aluminum-based alloys.
Alloys
Page on EM online book
Al87Ni7Cu3Ce3 page1433
Al72Ni20Co8 page1434

[1] P.A. Beck, L. T. Demer and M. L. Holzworth, Trans. Am. Inst. Min., Metall. Pet. Eng., 175 (1948) 372.
[2] William C. Mcbee, and John A. Mccomb, Grain Growth in Thin Aluminum-4% Copper Alloy Films, Thin Solid Films, 30 (1975) 137-143.

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