Measure Both Elastic and Viscous Properties with AFM
Product News Aug 29, 2014
Asylum Research has announced the availability of its powerful new nanomechanical imaging technique, AM-FM Viscoelastic Mapping Mode, for its entire line of Cypher™ and MFP-3D™ atomic force microscopes (AFMs).
AM-FM Viscoelastic Mapping Mode lets users quickly and gently image viscoelastic properties including storage modulus and loss tangent with nanoscale spatial resolution. The imaging mode is ideal for quantitative nanomechanical measurements on materials such as polymers, composites, biomaterials, ceramics, and metals.
“AM-FM Viscoelastic Mapping Mode is arguably the most powerful nanomechanical technique in Asylum’s NanomechPro™ Toolkit because it can measure both the elastic storage modulus and the viscous loss modulus or loss tangent over an extremely wide range of materials,” said Roger Proksch, President of Oxford Instruments Asylum Research.
Proksch continued, “AM-FM combines the features and benefits of normal tapping mode (AM) with quantitative, high sensitivity Frequency Modulation mode (FM). Because it’s based on normal tapping mode, it is simple and stable to operate, gentle enough for the softest samples and provides amazing high resolution images. It is also compatible with small cantilevers for fast scanning and reduced noise.”
AM-FM Mode gets results by operating at two cantilever resonances simultaneously. The first resonance is used for tapping mode imaging, also known as amplitude modulation (AM), while a higher resonance mode is operated in frequency modulation (FM). At resonance, the cantilever frequency and phase respond sensitively to changes in sample properties (i.e. stiffness, adhesion, loss tangent, etc.).
Small frequency and phase shifts can be measured with very high precision and accuracy, reducing uncertainty and increasing sensitivity. AM-FM offers quick visualization of relative contrast of sample components, and provides quantitative estimates of mechanical properties with Asylum’s built-in or customizable mechanical models. Its very wide operating range, from less than 1 MPa to hundreds of GPa, makes it a highly versatile and high resolution technique.