抄録
An evaluation method for contact of solid materials is proposed. Second harmonic ultrasonic component (SUHC) is detected to extract the information of interface of two glass plates. Dependence of second harmonic component (2MHz) for contact force (1-9 N), percentage of adhesive area (0-90%) and vibration amplitude (10nm-110nm) are respectively measured. As the results, nanometer order irregularity of the surface of contact becomes the source of SUHC and is strongly affected the second harmonic components ; SUHC is lineally increased to the contact force and is also increased to the percentage of tight adhesive area. Moreover, increase of SUHC is slight dependent to the vibration amplitude for healthy contacts, but has relatively strong dependency to the contact without contact agent. Necessity of explanation for behavior of SUHC should be considered at the view point of the sound reflection and transmission at the nanometer order gap between two glass plates are also suggested.