Elastic Microanalysis at Lower Temperatures

Abstract
Acoustic microscopy is wellknown nowadays as a powerful non-destructive tool to investigate the local elastic and structural properties of compact materials, composites and films. However, the application of commercial microscopes is limited to temperatures near ambient, because aqua dest. as a quite suitable immersion fluid is usually prefered. Here we report on our recent investigations, which are governed by the aim to extend elastic microanalysis to temperatures well below room temperature. All measurements are done between 90K and 230K by use of liquid propane as acoustic bonding medium. It is shown that elastic microanalysis at 1GHz can be successfully performed but is considerably affected by the strong temperature dependent properties of the coupling fluid chosen.