Dynamic Tensile Properties of Human Skin

The mechanical properties of skin are important for a number of applications including surgery, dermatology, impact biomechanics and forensic science. Studies have shown that the anisotropic effects of skin have been linked to sample orientation with respect to contour lines of tension, i.e.the Langer’s lines. There have been numerous studies undertaken to calculate the influence of Langer’s lines on the mechanical properties of human skin at quasistatic strain rates; however, it is relatively unknown what occurs at dynamic speeds. This study conducts a number of dynamic mechanical tensile tests to investigate the influence dynamic speeds have on the mechanical properties of human skin. The testing protocol involves uniaxial tensile tests at three different dynamic speeds, 1m/s, 1.5m/s and 2m/s, performed using an Instron tensile test machine. A total of 33 tests were conducted on 3 human cadavers aged 85, 77 and 82. Samples were excised at specific locations and orientations with respect to the Langer’s lines. The purpose for this was to recognize the significance that location and orientation have on the mechanical properties of human skin. The mean ultimate tensile strength (UTS) was 27.2±9.3MPa, the mean strain energy was 4.9±1.5MJ/m3, the mean elastic modulus was 98.97±97MPa and the mean failure strain was 25.45±5.07%. This new material data for human skin can be applied to constitutive models in areas such as impact biomechanics, forensic science and computer‐assisted surgery.

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