| 摘要 |
<p>Plectrum is a flat body of Be-Cu alloy containing more than 1% Be with a spring temper and with a picking edge spaced from a bend line transversely of the body. Body thickness and spring characteristics are such that it undergoes an initial deflection when forced against a string, followed by instantaneous and complete return to planar condition when released from the string. - The alloy pref. comprises 1.80-2.05% Be, 0.18-0.30% Co, remainder Cu, and the body has a tensile strength of 100,000-120,000 lb/sq.in and a Rockwell hardness of B-96 to 102. Body thickness is pref. 0.005-0.010 inch. The combination of thickness and properties provides optimum accuracy of plucking. (0/3)</p> |
