Instrumented nanoindentation is a valuable tool. It allows precision measurement of mechanical properties, even on individual grains or thick films. Though the concept began in the 1820’s with the Moh’s hardness scale, it has only matured since the 1980’s when computers and sensors made precise real-time measurement possible.
Since nanoindentation is relatively young, the scientific community is still improving its reliability and features. I helped contribute in two ways:
- Converting raw data into stress/strain curves
- Stress/strain curves give a much better picture of mechanical behavior than load/displacement, including the transition region between elastic and plastic deformation.
- Finding the Zero Point, where the tip hits the surface
- The zero point is critical to any measurement – being off by just 2 nanometers (nm) or 20 micro newtons (μn) can throw results (modulus, hardness, etc.) off by 15% or more.
The following publications provide more detail (Click Icons to Request Or Download):
 October 2006 Journal Article: On the determination of spherical nanoindentation stress-strain curves by S. Basu, A. Moseson and M. W. Barsoum in Journal of Materials Research (JMR)
January 2008 Journal Article: Determination of the effective zero point of contact for spherical nanoindentation by A. Moseson, S. Basu, and M. W. Barsoum in Journal of Materials Research (JMR) (Email for electronic copy)
 2007 Master’s Thesis: Spherical Nanoindentation: Insights And Improvements, Including Stress/Strain Curves and Effective Zero Point Determination, Drexel University
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Last Updated on Thursday, 11 September 2008 08:33 |
