January 2012, Issue 1 - Publication Spotlight

Publication Spotlight

This publication spotlight highlights a paper published in the November 2011 issue of Measurement Science and Technology. It is titled “The use of the PeakForce quantitative nanomechanical mapping AFM-based method for high-resolution Young’s modulus measurement of polymers,” and is authored by a highly regarded group of scientists mostly out of National Physical Laboratory (NPL) in the United Kingdom.

Focus of Article

In this paper, the authors carefully compare results from PeakForce QNM® traditional nanoindentating, in order to determine the new technique's accuracy and applicability to quantitative nanomechanical mapping. In the authors’ words, “The purpose of this investigation is to evaluate PeakForce QNM as a nanomechanical mapping technique to obtain valid modulus measurements for a range of polymers. The modulus values obtained from PeakForce QNM using different probes were compared with values measured using conventional instrumented (nano) indentation testing (IIT) and with the suppliers’ data.”

Their conclusion is that PeakForce QNM "results... were consistent and in reasonable agreement with IIT values for the majority of samples.”

PeakForce QNM Validation

Bruker launched PeakForce QNM after rigorous internal study. Now, independent study has proven PeakForce QNM’s capapbilities and why acceptance of PeakForce QNM as a quantitative nanomechanical mapping technique is growing within the community.

There have been several important papers highlighting PF QNM’s  quantitative capabilities (Schon et. al., Rico et. al.) however, this paper is quite significant because it:

1. Specifically compares PF-QNM to the generally accepted technique of nanoindentation
2. The entire paper is a pure study of the quantitative nature of PF-QNM
3. The paper uses 12 well-known and relevant polymers as its test samples (as opposed to less understood nano/bio samples), and
4. The authors are from the UK national standards institute, whose charter it is to study these exact types of standardization questions – see below.

About the Authors

Four of the six authors (T J Young, M A Monclus, T L Burnett, W R Broughton), including lead author (T J Young) are from the National Physical Laboratory (NPL) of the UK. NPL is the UK’s National Measurement Institute, and is a world-leading center of excellence in developing and applying the most accurate measurement standards, science, and technology available.
 
A Must Read for Anyone Involved With:

• Quantitative Measurement
• Polymer Science
• (Nano) Mechanical Properties
• (Nano) Indentation
• Contact Resonance Imaging
• Phase Imaging, Force Volume, Pulse Force Modes

Full article is available at iopscience (membership required) to go to their website click here.