Submitted to: Journal of American Leather Chemists Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/9/2014
Publication Date: 3/1/2015
Publication URL: http://handle.nal.usda.gov/10113/60451
Citation: Liu, C., Latona, N.P., Taylor, M.M., Eble, C.T., Ramos, M. 2015. Characterization of mechanical properties of leather with airborne ultrasonics. Journal of American Leather Chemists Association. 110(3):88-93.
Interpretive Summary: Since leather is sold by the square foot, destructive tests reduce the square footage available for sale and manufacturer’s total profit. Therefore, there is a need to develop an instrument to perform nondestructive testing of the mechanical properties of leather. We have developed a method using airborne ultrasonic (AU) to predict mechanical properties. This nondestructive method measures AU waves transmitted through the leather sample. We found that the transmission time of ultrasonic waves through leather is related to the mechanical properties of leather such as flexible strength, stiffness, fracture energy, and grain break of leather. This new method of testing leather is very important for quality control and assurance for the manufacturer.
Technical Abstract: A nondestructive method to accurately evaluate the quality of hides and leather is urgently needed by leather and hide industries. We previously reported the research results for airborne ultrasonic (AU) testing using non-contact transducers to evaluate the quality of hides and leather. The ability of AU testing was demonstrated for revealing defects in hides and leather that were difficult to be found during visual inspection. Recently, new research was carried out to develop AU methods to nondestructively characterize the mechanical properties of leather. Observations showed a strong correlation between the mechanical properties of leather and the corresponding AU parameters based on the distribution of the transmission time (time of flight) through leather. We also used this nondestructive method to characterize the grain break of leather. Results showed the difference in grain break could be determined from the AU parameters collected from moving the AU sensors over a leather sample. Observations showed the poorer the grain break, the higher the time of flight distribution. In short, this study demonstrated that the tensile strength, stiffness, toughness, and grain break could be nondestructively determined by AU.