Semina: Ciências Exatas e Tecnológicas (Jan 2002)
Speed of Sound and Materials Thickness Measuring by Ultrasound
Abstract
Nowadays, ultrasound pulse-echo systems are commonly used as a diagnostic tool, due to its advantageous characteristics such as being a non-destructive analysis method and having a millimeter range resolution for the currently used frequencies. Considering these and other qualities, this study intends to develop a system for measuring and analyzing physical properties of some materials. Using a data acquisition system in a microcomputer, electrical (voltage) pulses are generated to agitate a transducer that sends a pressure pulse towards the sample. This same transducer receives the echo reflected from the material, converts the mechanical energy into an electrical one, transforming it into information, which is processed later using a mathematical computer program. With this process, the values of the sound speed and the signal attenuation in the sample are obtained, plus its thickness with a minor error.