Characterization of Indentation-induced ‘Particle Crowding’ in Metal Matrix Composites

Abstract

A direct experimental characterization of reinforcement configuration in an indentation-deformed metal matrix composite is undertaken. The primary objective is to quantify the possible local increase in particle concentration, which has been proposed to cause inconsistency in the indentation hardness and the overall composite strength. Quantitative metallography on the post-indented material is carried out to measure the particle volume fraction. Multiple cross sections of an indentation are investigated with the statistically significant results obtained. A distinct increase in particle concentration induced by the indentation is found. The spatial distribution of particle concentration is also examined in detail. The residual compressive stress field remained in the material upon unloading, as illustrated by the finite element analysis, is shown to be in qualitative agreement with the measurement.

Get full access to this article

View all access options for this article.

References

Bolshakov, A. , Oliver, W.C. and Pharr, G.M. (1996). Influences of Stress on the Measurement of Mechanical Properties using Nanoindentation. 2 . Finite element simulations. J. Mater. Res., 11: 760-768 .

Caceres, C.H. and Poole, W.J. (2002). Hardness and Flow Strength in Particulate Metal Matrix Composites . Mater. Sci. Engng. A, 332: 311-317 .

Chawla, N. , Andres, C. , Jones, J.W. and Allison, J.E. (1998). Effect of SiC Volume Fraction and Particle Size on the Fatigue Resistance of a 2080 Al/SiCp Composite . Metall. Mater. Trans. A, 29A: 2843-2854 .

Chawla, N. , Habel, U. , Shen, Y.-L. , Andres, C. , Jones, J.W. and Allison, J.E. (2000). The Effect of Matrix Microstructure on the Tensile and Fatigue Behavior of SiC Particle-Reinforced 2080 Al Matrix Composites . Metall. Mater. Trans. A, 31A: 531-540 .

Cheng, Y.-T. and Cheng, C.-M. (1999). Can Stress-Strain Relationships be Obtained from Indentation Curves Using Conical and Pyramidal Indenters? J. Mater. Res., 14: 3493-3496 .

Dao, M. , Chollacoop, N. , Van Vliet, K.J. , Venkatesh, T.A. and Suresh, S. (2001). Computational modeling of the forward and reverse problems in instrumented sharp indentation , Acta Mater., 49: 3899-3918 .

Ege, E.S. and Shen, Y.-L. (2003). Effects of inclusions and porosity on the indentation response . In: Kumar, A. , Meng, W.J. , Cheng, Y.T. , Zabinski, J.S. , Doll, G.L. and Veprek, S. (eds), Surface Engineering 2002 - Synthesis, Characterizations, and Applications, Mater. Res. Soc. Symp. Proc., Vol. 750, p. U6.2 .

Fisher-Cripps, A.C. (2002). Nanoindentation, Springer Verlag, New York .

Gupta, M. (1998). Effect of Precipitation on the Bulk Hardness and the Ultimate Tensile Strength of a 6061/SiC Composite . High. Temp. Mater. Processes, 17: 237-243 .

10.

Kim, H.S. (2000). On the Rule of Mixtures for the Hardness of Particle Reinforced Composites . Mater. Sci. Engng. A, 289: 30-33 .

11.

Kim, H.S. , Bush, M.B. and Estrin, Y. (2000). A Phase Mixture Model of a Particle Reinforced Composite with Fine Microstructure . Mater. Sci. Engng. A, 276: 175-185 .

12.

Kozola, B.D. and Shen, Y.-L. (2003). A Mechanistic Analysis of the Correlation Between Overall Strength and Indentation Hardness in Discontinuously Reinforced Aluminum . J. Mater. Sci., 38: 901-907 .

13.

Kucharski, S. and Mroz, Z. (2001). Identification of Plastic Hardening Parameters of Metals from Spherical Indentation Tests . Mater. Sci. Engng. A, 318: 65-76 .

14.

Mata, M. and Alcala, J. (2004). The Role of Friction on Sharp Indentation, J . Mech. Phys. Solids, 52: 145-165 .

15.

Shen, Y.-L. and Chawla, N. (2001). On the Correlation Between Hardness and Tensile Strength in Particle Reinforced Metal Matrix Composites . Mater. Sci. Engng. A, 297: 44-47 .

16.

Shen, Y.-L. , Fishencord, E. and Chawla, N. (2000). Correlating macrohardness and tensile behavior in discontinuously reinforced metal matrix composites , Scripta Mater., 42: 427-432 .

17.

Shen, Y.-L. and Guo, Y.L. (2001). Indentation modelling of heterogeneous materials, Modelling Simul . Mater. Sci. Engng., 9: 391-398 .

18.

Shen, Y.-L. , Williams, J.J. , Piotrowski, G. , Chawla, N. and Guo, Y.L. (2001). Correlation between tensile and indentation behavior of particle-reinforced metal matrix composites: an experimental and numerical study , Acta. Mater. 49: 3219-3229 .

19.

Vander Voort, G.F. (1984). Metallography - Principles and Practice, p. 426, McGraw-Hill, New York .