Acoustic emission studies for leather coatings

Finishing, the final step in the leather-making process, contributes to the beauty and durability of leather. Choosing the right coating is critical in obtaining a satisfactory finishing result, such as good flexing endurance and no surface cracking. Acoustic emission has been known to be a useful method to characterize the coating properties for the automobile industry. As a continuation of our efforts to investigate the applications of acoustic emission technology to leather manufacture, we exploited the AE technique to measure the flexing endurance of leather coatings. An acoustic sensor was clipped to the grain layer of finished leather in a tensile test to collect various acoustic quantities. Observations showed that differences in the flexibility of the coatings can be analyzed by examining the plot of the AE count rate as a function of time. We have concluded that a quantitative association exists between the flexibility of coatings and the cumulative acoustic counts produced at an initial tensile stretch. The results of this AE research may provide a route to examine the flexing endurance of leather coatings.