Nanometer-to-micrometer Length Scale Mechanical and Tribological Characterization System

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Surface properties (wear resistance, hardness, surface deformation) are critical to the performance requirements of many components and devices, such as biomedical devices and aerospace applications. To establish a relation between nano- and microstructure and mechanical response of material surfaces, it is important to be able to characterize local structural deformations at high resolution using nanomechanical testing for a broad range of tailored surface chemistries, films or coatings. This proposal requests a robust and all-encompassing advanced nanoindentation system (Bruker TS 77 Nanoindenter) which features an in-situ Scanning Probe Microscopy (SPM) visualization system, to simultaneously perform SPM imaging of a material surface structure, while performing nano-micrometer length scale mechanical and tribological analysis. Nanoindentation has become a powerful alternative to measure elastic modulus, hardness, creep, stress relaxation, and fracture toughness at small scales, with full control over the indenter loading and unloading rates, dynamic oscillation, peak load, and other test parameters. This technique is not limited only to surface engineering technologies but can also be used to investigate the nanometer-to-micrometer length scale mechanical and tribological behaviour of materials in general, such as: analysis of different phases in multi-phases materials, fibre-matrix interfaces in composite materials and microstructural analysis of bulk materials. The TS 77 has the unique feature of using the same probe to raster the sample surface for topography imaging (SPM) as it does to conduct the nanomechanical test, which facilitates the positioning on desired testing sites. This ability to visualize the sample surface on the same length scale as the testing grant superior nanomechanical characterization results and data reliability. Thus, nanometer precision test placement accuracy can be achieved, which ensures that the test is being conducted at the exact desired location on the material. Additionally, by using the in-situ SPM imaging capabilities on the TS 77, quantitative wear volumes and wear removal rates can be measured as a function of applied contact force, sliding speed, and number of passes, which cannot be performed in a traditional nanoindenter system. Due to the scale of testing, tribological performance of individual microstructures, interfaces, and thin films can readily be measured. Currently, there are no in situ SPM imaging nanoindentation systems available in the Toronto region. We suggest the TS 77 will be of significant value for the research, design, and optimization of engineered materials, within the academic research and industrial communities.