Nanoscratch testing is a versatile tool for analysis of both thin films and bulk materials. Nanoscratch provides the capability to investigate modes of deformation and fracture that are not possible using standard indentation techniques. Nanoscratching is accomplished by applying a normal load in a controlled fashion while measuring the force required moving the tip laterally across the sample. By selecting the appropriate normal loading profile and lateral displacement pattern, many different types of tests can be performed. The damage incurred from the test is then typically observed using optical or Scanning Probe Microscopy (SPM) imaging. Hysitron provides in-situ SPM imaging of the sample with nanometer resolution for immediate feedback of the test results.
Figure 1. Nanoscratch of a low-k film, showing evidence of film failure
Figure 2. Nanoscratch data on a protective coating on glass showing point of delamination (red arrow) and the associated friction measurement
Nanoscratch can be used for such a plethora of tests that a versatile load function editor is necessary. Hysitron has created an easy-to-use software product that was designed by experimentalists for experimentalists. This software for the nanoscratch product allows the user to define the applied normal load and the lateral displacement across the surface of the sample. A single scratch with a ramped normal load, as seen above, is useful for critical load, film adhesion and mar studies, to name a few.
Alternatively, the software can be used to generate a load function that repeatedly scratches over the surface of the sample with a defined normal load, thus enabling reciprocating wear testing. Nanoscratch data, in conjunction with in-situ images, provides a wealth of information concerning a materials behavior under simultaneous normal and lateral stresses.
Analysis of nanoscratch data is most commonly done by utilizing the normal and lateral load and displacement data in conjunction with an image of the scratch or wear track. Hysitron’s exclusive in-situ imaging allows quantification of scratch dimensions with nanometer resolution. This information can be utilized to study many properties.
· Scratch resistance
· Wear resistance
· Friction coefficient
· Critical load
· Mar resistance
· Disk drives: How well does the protective and lubricating film protect the hard disk.
· Paints: How resistant is a paint coating to marring.
· Optical fibers: How well do the polymer layers protect the glass fiber from wear.
· Contact lenses: Characterize the polymer layers on the lens material.
· Lubrication layers: Quantify friction coefficients.
· Medical implant materials: Measure wear rate of UHMWPE materials.
· Hysitron systems provide in-situ SPM imaging capabilities for unparalleled nanoscratch testing precision and analysis.
· Flexible software package enables multiple modes of nanoscratch testing.
· TriboView® software offers features that allow for automated quantification of wear volumes.
· Nanoscratch system utilizes the same transducer design as quasistatic testing, recognized for its proven stability and sensitivity.
Figure 3. Reciprocating wear test performed on the TriboIndenter investigating wear resistance of a wear-resistant material
· Nanoscratch testing is included with all TriboIndenter® systems and can be added to any TriboScope® or Ubi 1® system.
· Nanoscratch results can be compared to microscratch results on the same sample and the same instrument.
· Hysitron provides a wide selection of diamond tip geometries optimized for any nanoscratch application.