The Comparison of Mechanical Properties of Topneck Mollusks Shell Nano Composite in Different Conditions

The mechanism of biological materials structure is very complex and has optimal properties compared to engineering materials. Topneck mollusks shells, as an example of biological materials, have hierarchical structure, which 95 percent of its structure is Aragonite and 5 percent organic materials. This article tries to detect mechanical properties of the Topneck mollusks shell as a nano composite using Nano-indentation method in different situations. Research findings indicate that mechanical properties of the Topneck mollusks shell including elastic modulus and hardness are higher than a fresh one preserved in -50 centigrade and also a Topneck mollusks shell preserved in environmental conditions. Nano-indentation test results are so close in range, overall, that hardness degree is 3900 to 5200 MPa and elastic modulus is 70 to 85 GPa.