Introduction

This page describes the protocol to be followed when performing ultrasonic testing for the MOST Research Group at Michigan Technological University. The ultrasonic testing can be used to find out the Poisson's ratio of a material. You can also determine the Young's modulus and the shear modulus of a material.

Test specimen

The test specimen MUST have 2 flat surfaces of at-least 1 inch diameter (It can be any shape). The surfaces must be smooth.

Theory

Test lab and apparatus

The ultrasonic testing is done in room U208. The apparatus consists of Computer Longitudinal Piezoelectric emitter/receiver (Green) Transverse Piezoelectric emitter/receiver Ultrasonic pulse emitter Buffer solutions:

The ultrasonic pulse emitter is already set to the required values. Do not change any properties unless you know what you are doing.

Connect one Piezoelectric emitter/receiver to the pulse emitter. Apply some buffer solution to the specimen (a drop is enough) Press the emitter/receiver end on the specimen, (at the point where buffer solution is applied). Turn on the Ultrasonic pulse emitter.

The software shows Pulses received vs Time(X axis). The time axis can be scaled as required, usually around 1-4 Microseconds. At a particular scale of time, the pulses received are clearly visible and the time between two pulses received can be measured. To measure the time between two pulses, pause the software (so that values do not change) and click at one pulse (peak of the pulse) and drag the mouse to the next pulse. The time and frequency will be shown near the bottom left side in the software. Note it down.

Repeat for the other Piezoelectric emitter/receiver