Handbook-Appendices

3 Appendix B Physical Properties of Metals A. Chemical symbol. (Many of the symbols are derived from Latin names for the elements; for example, ”Pb” from ”plumbum”, ”Au” from ”aurum”, and ”Sn” from ”stannum”.) B. Specific gravity; the relative mass of the metal by comparison with water. Since one cubic meter of water has a mass of 1000 kilograms, the density of any of the metals, in terms of kg/m³, is 1000 times the figure shown. To arrive at density in terms of pounds per cubic foot, multiply specific gravity by 62.5. C. Melting point, degrees Celsius. D. Melting point, degrees Fahrenheit. E. Coefficient of thermal expansion, per degree C, X one million. To illustrate use of these figures: An unrestrained bar of aluminum, one meter long, will change its length 23.6 millionths of a meter (or 23.6 thousandths of a millimeter) for each 1⁰C change in temperature. Rate of expansion is not constant at all temperatures; data given represent coefficients at room temperature. F. Thermal conductivity. Specifically, the figures shown represent calories per square centimeter cross-section, per centimeter length, per degree C. (Cal/cm²/cm/⁰C). Data provided primarily to emphasize the wide variation in thermal conductivity, and fact that there is no general relationship between rate of expansion and rate of heat conductivity. A B C D E F Aluminum Al 2.70 658 1216 23.6 .57 Chromium Cr 7.14 1615 2939 6.2 .16 Copper Cu 8.94 1083 1981 19.6 .94 Gold Au 19.3 1063 1945 14.2 .71 Iron Fe 7.86 1535 2795 11.7 .18 Lead Pb 11.35 328 622 29.3 .08 Magnesium Mg 1.74 651 1204 25.2 .37 Nickel Ni 8.90 1452 2646 13.3 .22 Platinum Pt 21.5 1755 319 18.9 .16 Silver Ag 10.5 960 1760 19.7 1.0 Tin Sn 5.75 232 450 23 .15 Titanium Ti 4.5 1800 3272 8.4 .04 Tungsten W 19.3 3370 6098 4.6 .40 Zinc Zi 7.14 419 787 39.7 .27