MNSMS  Vol.4 No.4 , October 2014
Numerical and Experimental Study of the Roughness Effects on Mechanical Properties of AISI316L by Nanoindentation
Abstract: Surface roughness is a commonly used criterion for characterization of surface quality in a machining operation. In the study of micro-scale mechanical properties of machined surface and cutting tool using nanoindentation method, perfect surface finish on the specimen is often required for the reliable indentation result. However, the perfect surface finish is often difficult to obtain from the machining operation due to the dynamic behavior of the machining and the limitation of the cutting tool geometry. In the presented paper, the effect of surface roughness on the nanoindentation measurements is investigated by using finite element method. A 3D finite element model with seven levels of surface roughness is developed to simulate the load-displacement behavior in an indentation process with a Berkovich indenter. The material used in the simulation is AISI 316 L stainless steel, modeled as an elastic-plastic material. The mechanical properties were calculated by combining simulations with the Oliver-Pharr method. The hardness and reduced modulus from the simulation were found to decrease with an increase of roughness. The study showed that the scatter of the load-depth curves and the deviation of the hardness and the reduced modulus are significant affected by the variation of roughness. It was also found that the height of pile-up was little affected by the surface roughness from the simulation. The combined effect of indenter tip radius and surface roughness was also investigated. The study was complemented with experimental tests and the results from these tests support the results from the simulation.
Cite this paper: Chen, L. , Ahadi, A. , Zhou, J. and Ståhl, J. (2014) Numerical and Experimental Study of the Roughness Effects on Mechanical Properties of AISI316L by Nanoindentation. Modeling and Numerical Simulation of Material Science, 4, 153-162. doi: 10.4236/mnsms.2014.44017.

[1]   ISO (2002) Metallic Materials—Instrumented Indentation Test for Hardness and Materials Parameters —Part 1: Test Method, in Part 1: Test method Iso. Geneva, Switzerland.

[2]   Warren, A.W. and Guo, Y.B. (2006) Machined Surface Properties Determined by Nanoindentation: Experimental and FEA Studies on the Effects of Surface Integrity and Tip Geometry. Surface & Coatings Technology, 201, 423-433.

[3]   Bhushan, B., Gupta, B.K. and Azarian, M.H. (1995) Nanoindentation, Microscratch, Friction and Wear Studies of Coatings for Contact Recording Applications. Wear, 181, 743-758.

[4]   Fischer-Cripps, A.C. (2011) Nanoindentation. 3rd Edition, In: Ling, F.F., Ed., Mechanical Engineering, Vol. 1, Killarney Heights, New South Wales, 272.

[5]   Bobji, M.S., Shivakumar, K., Alehossein, H., Venkateshwarlu, V. and Biswas, S.K. (1999) Influence of Surface Roughness on the Scatter in Hardness Measurements—A Numerical Study. International Journal of Rock Mechanics and Mining Sciences, 36, 399-404.

[6]   Walter, C., Antretter T., Daniel, R. and Mitterer, C. (2007) Finite Element Simulation of the Effect of Surface Roughness on Nanoindentation of Thin Films with Spherical Indenters. Surface and Coatings Technology, 202, 1103-1107.

[7]   Bolesta, A.V. and Fomin, V.M. (2009) Molecular Dynamics Simulation of Sphere Indentation in a Thin Copper Film. Physical Mesomechanics, 12, 117-123.

[8]   Shibutani, Y. and Koyama, A. (2004) Surface Roughness Effects on the Displacement Bursts Observed in Nanoindentation. Journal of Materials Research, 19, 183-188.

[9]   Gascón, F. and Salazar, F. (2011) Simulation of Rough Surfaces and Analysis of Roughness by MATLAB. In: Ionescu, C.M., Ed., MATLAB—A Ubiquitous Tool for the Practical Engineer, InTech, Rijeka, 391-420.

[10]   Wu, J.J. (2000) Simulation of rough surfaces with FFT. Tribology International, 33, 47-58.

[11]   Nascimento, F.C., Foerster, C.E., da Silva, S.L.R., Lepienski, C.M., Siqueira, C.J.D. and Alves, C. (2009) A Comparative Study of Mechanical and Tribological Properties of AISI-304 and AISI-316 Submitted to Glow Discharge Nitriding. Materials Research-Ibero-American Journal of Materials, 12, 173-180.

[12]   Pelletier, H., Krier, J., Cornet A. and Mille, P. (2000) Limits of Using Bilinear Stress-Strain Curve for Finite Element Modeling of Nanoindentation Response on Bulk Materials. Thin Solid Films, 379, 147-155.

[13]   Chen, L., Ahadi A., Zhou, J. and Stahl, J.-E. (2012) Characterization of Mechanical Properties of Machined Surface by Nanoindentation—Part 1: Simulation of Indenter Geometry Effects, in SPS12LUCATORG: 011201100. Linkoping, 191-198.