Microstructure and nanomechanical properties of foreleg surface of the praying mantis ( Mantis religiosa Linnaeus)

Abstract

Detailed investigations on the microstructure and mechanical properties of the surface of the praying mantis’ foreleg were carried out in this work since the microstructure and mechanical properties of insect organisms surface are well adjusted to their functions. Scanning electron microscopy revealed the surface microstructures of the tibia and femur were composed of squamous fibre and the spine surfaces on these two parts are arris. A nanoindenter was used to investigate the mechanical properties of the praying mantis's foreleg, including the mean Young's modulus and hardness of the femur cuticle, tibia cuticle and the apical claw. The test results on these parts were E = 5.533 GPa, H = 0.239 GPa, E = 3.471 GPa, H = 0.186 GPa, E = 2.232 GPa, H = 0.449 GPa, respectively. The variation of mechanical properties agreed with the analysis of microstructure.