| 摘要 |
PURPOSE:To prevent the deterioration of sound quality and the deterioration of operation and to obtain faithful reproduced sound at a low price by constituting the acoustic lens of the material composed of the high damping aluminum alloy of Al-Si system whose damping capacity is set to 8-10 or Al-Ni system. CONSTITUTION:In the Al-Si system high damping aluminum alloy, a Si particle in an Al of matrix is precipitated when the Si is mixed in the Al to form eutectic crystal. The interface of the second phase Si particle absorbs oscillation, and improves the damping capacity Q<-1>. In the Al-Ni system high damping aluminum, the Ni particle is precipitated in the Al of matrix when the Ni is mixed in the Al to form eutectic structure. The interface of the second phase Al3 Ni particle absorbs the oscillation and improves the damping capacity Q<-1>. Thus, the effect of vibration isolation can be enlarged while maintaining rigidity, and high quality lens with unnecessary radiation can stably be obtained by the same operation as the conventional one in a low price. |
