The acoustics of friction and microstructure of model and apparel fabrics

Apparel fabrics are constructed of large numbers of fibers, spun into thread and woven and treated with sizing into final structures, giving rise to a number of different surface properties. A method to record and analyze the friction sound emitted from model fabrics (uniform, single-fiber polyester meshes) and apparel fabrics was developed and the relationship between microstructure and the sound emitted was established. The effect that surface modification (conditioning) has on sound emission was also investigated. Fabric sounds were captured as a result of friction, producing sound spectra (frequency versus amplitude), from which total noise could be calculated. This was compared to the fabrics' microstructure. The shape of the sound spectra varied as a result of the structure of the model fabrics, with experimentally measured frequencies being comparable to predicted frequencies calculated. It is possible to produce a ‘fingerprint’ of acoustics, based on the thread diameter and aperture size of single-fiber structures. Spectra produced for apparel fabrics were broader than for the model fabrics (possibly as a result of the multifiber structure), and the level of total noise differed between the three fabrics, with total noise being strongly correlated to surface roughness and weight. A relationship between the total frictional noises emitted from surfaces of different materials has previously been investigated. Conditioning fabrics, no treatment and desizing the fabrics did not have a significant effect on surface roughness, weight or total noise.