NanoRack™ Sample Stretching Stagefor the MFP-3D™ AFM

Introduction

AFMAsylum Research

The NanoRack Sample Stretching Stage provides the first direct measurement method for observing nanoscale features andeffects of materials under stress control. The NanoRack stage is available as an option for MFP-3D AFMs.

The NanoRack stage (Figure 1) is a high-strain, high-travel
manual tension and compression stage that provides twoaxis stress control of samples under different loads. It
integrates force measurements with AFM images or othermeasurements and returns both stress and strain data. Thestage is compatible with a wide variety of imaging techniques
including Phase and Dual AC™ for enhanced contrast ofmaterial properties, as well as our Ztherm™ option for
localized thermal analysis. The height-adjustable stabilizing
pillar can be removed to provide bottom access to the test
sample. The NanoRack is ideal for a wide range of applications
including measurements of adhesive strength in polymers
and stress-induced deformations and cracking in a varietyof biological and inorganic materials.

Features/Benefitsl H
 igh-strain, high-travel manual stretching stageprovides two axis tensile stress control
l Returns both stress and strain datal C an be used under tension or compressionl A llows control of the sample image region under
different loads

Figure 1: The MFP-3D NanoRack Sample Stretching Stage is ahigh-strain, high-travel manual stretching stage that provides
control of tensile and compressive loaded samples up to 80 N.

a direct determination of interfacial adhesion in complex
polymer-containing materials such as ICP. Studies of this kind
improve our understanding of material structure-property
relationships, ultimately enabling manufacture of better
quality products.
Figure 2 shows real-time stress vs. time curves of the ICP as
the sample is being pulled in the NanoRack. Note that theforce spikes immediately upon pulling and is followed by alengthy relaxation process that is strongly material dependent.
As the copolymer stretches, the individual components (PPand EP rubbers) deform accordingly in response to the tensilel S martStart™ automatic load cell calibration provides
integrated force measurements with MFP-3D images
or other measurementsl C ompatible with a wide variety of Asylum Research
imaging techniques including Phase and Dual AC,
as well as Ztherm Modulated Thermal Analysis

Impact Copolymer Example
A commercial impact copolymer (ICP), a multicomponent
material typically used in automotive and applianceapplications where a balance of stiffness and toughness
is needed, was studied with the NanoRack accessory on
the MFP-3D AFM to investigate material deformation andinterface adhesion as a function of tensile stress. Effects ofdeformation were observed within both the polypropylene(PP) and ethylene-propylene (EP) components, as well asat the interface between the two materials.
There are no other direct measurement methods available todetermine interfacial adhesive strength of polymer blends,
and so AFM investigations of micro-domain deformation suchas the one described here could be used ultimately to provide

1

Figure 2: Stress (Newtons) vs. time (seconds) curve of ICP as it is being
stretched on the NanoRack.

stress. Figure 3 shows before and after images of the EPcomponent for a 3% elongation. For additional information,see our application note “Applications of the NanoRack Sample
Stretching Stage to a Commercial Impact Copolymer” byD. Yablon, et al., ExxonMobil.

Crack Propagation in Bone Example
Due to the hierarchical structure and complexity of bone, theuncovering of structure-function relationships, i.e. the originof material properties such as strength, toughness, and fatigue
resistance, is usually a non-trivial task. The NanoRack Sample
Stretching Stage, in combination with AFM imaging, offers anapproach to overcome some of these difficulties. Because AFM
allows for imaging in ambient – even hydrated conditions –it is feasible to perform in situ micro-mechanical testing
experiments while conducting imaging. Figure 4 shows cracking
generated in a cortical bovine bone. As expected, due to theunderlying lamellar structure, such cracking under stress isgenerally deflected towards the long beam axis. For additional
information, see our application note “Crack Propagation inBone Captured with In Situ Mechanical Testing During AFM”,
O. Katsamenis, et. al, University of Southampton.

Figure 3: Amplitude mode 2 images of identical EP domain within ICP
material at (a) neutral position on NanoRack and (b) 3% elongation on
NanoRack. 5 µm scans.

Specificationsl S ample Size: 12 mm wide maximum, 41 mm long minimum,
6 mm thick maximuml S ample is supported by a height-adjustable stabilizing
pillar that can be removed to provide bottom accessto the test sample

Figure 4: AFM height (left) and amplitude (right) images showing
a crack in cortical bovine bone deflecting and eventually breaking
through a lamella. 24 µm scan.

l M aximum range of motion: 120 mm (30 mm relaxedto 150 mm fully stretched)l M aximum 80 N load (strain gauge limit)l S train (force) gauge can be swapped from a 80N (±0.8N)
version to 20 N (±0.2 N) version for higher resolution atlower forcesl K
 nobs adjust sample 500 µm per revolutionl Can discretely adjust to 5 µm encoder resolution

Compatibilityl C ompatible with all MFP-3D AFMs except MFP-3D Origin.™

Visit www.AsylumResearch.com to learn more
The foregoing datasheet is copyrighted by Oxford Instruments Asylum Research, Inc. Oxford Instruments Asylum Research, Inc. does notintend the datasheet or any part thereof to form part of any order or contract or regarded as a representation relating to the products
or service concerned, but it may, with acknowledgement to Oxford Instruments Asylum Research, Inc., be used, applied or reproduced
for any purpose. Oxford Instruments Asylum Research, Inc. reserves the right to alter, without notice the specification, design orconditions of supply of any product or service. Data Sheet 37 – 6/2014.

6310 Hollister Avenue
Santa Barbara, CA 93117
Voice+1 (805) 696-6466
Toll free +1 (888) 472-2795
Fax+1 (805) 696-6444

www.AsylumResearch.com
info@AsylumResearch.com
sales@AsylumResearch.com

FSC® C020739