The Use of Ultrasound for the Investigation of Rough Surface Interface

Perthometer is an instrument used for the measurement of surface roughness, externally and some intricate internal parts. The stationary part of this instrument gives the details of the surface roughness by using the grit numbers and graph which is helpful at a certain extent. This paper makes the use of disadvantage of Perthometer that, the readings give the details of the surface roughness in the form of grit numbers and only the external flat surfaces can be inspected by this instrument. To overcome this disadvantage, we are using ultrasonic investigation of surface roughness. The sensitivity of the ultrasonic technique has been quantified using a simple model, from which the stiffness of individual gaps and contacts are calculated and their effects on the ultrasonically measured stiffness predicted. The reflection of ultrasound at a static interface between rough surfaces can be investigated. The effect of surface roughness on the resultant contact can also be investigated. However, it is clear that the model is a powerful non-destructive tool to evaluate surface roughness in an easier way.