Nanoindentation tests of Sulcata Tortoise's carapace

8th TSME-International Conference on Mechanical Engineering

Jongpairojcosit, Nadda^1,2 ; Jearanaisilawong, Petch^1

Department of Mechanical and Aerospace Engineering, Faculty of Engineering King Mongkut's, University of Technology North Bangkok, 1518 Pracharat 1 Rd, Wongsawang, Bangsue, Bangkok

10800, Thailand^1

Defence Technology Institute (Public Organization), Ministry of Defence Office of the Permanent Secretary of Defence (Chaengwattana), 47/433 Moo 3, Ban Mai, Pak Kret, Nonthaburi

11120, Thailand^2

关键词: Hardness and elastic modulus;    Nanoindentation tests;    Peak load;    Porous layers;    Sandwich-like structure;    Submicron;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/297/1/012016/pdf
DOI  :  10.1088/1757-899X/297/1/012016

来源: IOP

【 摘 要 】

This paper illustrates the dependence of tortoise carapace's hardness and elastic modulus on peak-load of nanoindentation tests. Sulcata Tortoise carapace is a sandwich-like structure consisting of four submicron layers: keratin scutes, dorsal cortex, cancellous interior (porous layer) and ventral cortex. Nanoindentation test is a viable option for measuring their mechanical properties due to the size of the layers. However, preliminary results of nanoindentation tests on a carapace sample vary according to the indentation peak load. As the indentation peak load increases, both measured hardness and elastic modulus decrease. A systematic approach to determine an optimal peak load for nanoindentation test is presented.