The physical properties of fingernails I. Apparatus for physical measurements

Miniature APPARATUS for measuring the PHYSICAL PROPERTIES of FINGERNAILS have been developed and tested. Included are a device for cutting test specimens; a template for preparing tensile bar samples; apparatus for performing flexural, tensile, and tearing tests; and a device for determining impact absorption. Whenever possible, methods were based on standard testing procedures so that recognized in-terpretative formulae could be used for analyzing experimental results. The range of physical properties found for the fingernails tested are as follows: flexural strength 4,928 to 17,653 psi; tensile strength 4,464 to 17,081 psi; tearing resistance 274.3 to 676.2 lb/in. and impact absorption (rebound ratio) 0.4632 to 0.7273