Effect of Poisson’s Ratio on Material Properties Characterization by Nanoindentation with a Cylindrical Flat Tip Indenter

by MD Mehadi Hassan

Institution: South Dakota State University
Year: 2016
Keywords: cylindrical flat-tip indenter; finite element analysis; material properties; maximum pile up; nano indentation; Poisson’s ratio; Materials Science and Engineering; Mechanical Engineering
Posted: 02/05/2017
Record ID: 2132267
Full text PDF: http://openprairie.sdstate.edu/etd/1020


Nano indentation technology is commonly used to determine the mechanical properties of different kinds of engineering materials. The young’s modulus of the materials can be calculated with the load depth data obtained from an indentation test with a known Poisson’s ratio. In this investigation the NANOVEA micro/nanoindentation tester with a cylindrical flat-tip indenter will be used to find the elastic modulus, hardness and Pile up. Low carbon steel AISI1018, alloy steel AISI 4340 and aluminum alloy 6061 were selected for the case study. Finite element (FE) analysis using axisymmetric 3-D models used to establish the relationship between Poisson’s ratio and the deformation of indentation / materials strain hardening exponential index with a cylindrical flat tip indenter. The modeling was done by considering the Poisson ratio ranging from 0 to 0.48 in order to find the influences of Poisson ratio on the elasticplastic properties was verified by associated experimental results. From the modeling results, it was found the indentation depth has very little effect on calculating the elastic modulus of the sample material in the same Poisson ratio and the hardness slowly increases with the increase of maximum indentation depth as well as increase the Poisson ratio. The maximum pile up value for the three materials decreases with the decrease of Poisson ratio that was very sensitive. Advisors/Committee Members: Zhong Hu.