Abstract
In view of the high cost, healthy-concern and environmental safety of conventional copper-beryllium alloy, the invention provides a kind of beryllium-free multi-element copper alloys. The copper content of this kind alloy is between 45 and 80 by atomic percentage. The rest must contain at least four elements: Al, Cr, Fe and Ni to cause solution hardening, dispersion hardening and precipitation hardening. Alumnium content is between 4 and 17 by atomic percentage. Nickel content is between 3 and 19 by atomic percentage. Both Cr and Fe contents are at least 0.5 by atomic percentage but their total content is between 2 and 26 by atomic percentage. In addition, the alloy could be further strengthened by adding at least one selecting from the group of Sn, Co, V, Ti, Mn, Zn, Pb, Ge, C, P, Mg, Ce, Y, La, B, Sb, Zr, Mo, Si, and Nb. The total content does not exceed 15 by atomic percentage. By the measurement of hardness values, the invention provides many experimental examples of beryllium-free copper alloys which show their hardness could exceed HV200. As a result, the beryllium-free copper alloys could replace copper-beryllium alloys in the applications including polymer injection molds, conductive springs, heat dissipaters, electrodes, non-spark tools, bearings, gears, pistons.