J0420405 密着圧力による界面波速度分散の変化の計測([J042-04]超音波計測・解析法の新展開(4),機械材料・材料加工部門)

Abstract

A contact pressure dependence on group velocity dispersion of interface waves was measured for experimentally discussing contact condition of two aluminum alloy plates with a low stiffness layer (0.3 mm-thick silicone rubber sheet) as an intermediate layer under compressive loads. The interface waves were produced by converting Rayleigh wave generated by an angled transducer and were detected after transmitting thorough the interface. At a contact pressure of 1.6 kPa, the group velocity of the interface wave was constant in the frequency range of 0.5 MHz to 1.5 MHz and was almost the same as that of Rayleigh wave propagating on the aluminum alloy substrate. Meanwhile, the group velocity of the interface wave at 3 MPa decreased with increasing frequency and showed similar behavior to a theoretical dispersion of the anti-symmetric mode in an interface waves. It is confirmed that the propagation behavior of the interface wave strongly reflected the contact pressure at the interface.