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Mechanical properties of the orthorhombic phase of YBa2Cu3O7−δ (Y123) at room temperature have been investigated at different applied loads: 5, 10, 30 and 100 mN using a nanoindentation technique. This study was carried out for different monodomains on the (001) plane for textured Bridgman samples with dispersed particles of Y211 as pinning centres. Hardness and Young’s modulus values were calculated using the Oliver–Pharr approach. Nanohardness and Young’s modulus for the Y123, Y2BaCuO5 (Y211) and Y 123/Y 211composite (YBCO) were determined using an applied load of 5 and 10 mN. For higher loads, it is not possible to differentiate the matrix (Y123) from the precipitates (Y211). In this case, only hardness and Young’s modulus of the YBCO composite can be determined. Finally, the ultra-low load imprints obtained by nanoindentation have been correlated with parameters obtained by atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM).

This paper studies the correlation between the microstructure and the mechanical properties at the nanometric length scale of individual WC grains as well as the metallic cobalt binder in cemented carbide systems. The local crystallographic orientation has been determined by electron backscattered diffraction and the microstructural analysis has been performed using field emission scanning electron microscopy. Small-scale hardness and elastic modulus have been assessed by means of high speed massive nanoindentation and subsequent statistical analysis. The attained mechanical property mappings present a clear correlation between local hardness and stiffness with chemical nature for each constitutive phase as well as with the crystallographic orientation for the WC particles. Besides expected findings associated with individual phases, such as clear anisotropy of the ceramic phase (basal plane being harder and stiffer than the prismatic one) and relatively high flow stress for constrained binder, the protocol implemented provides novel information on local mechanical response at interfaces between ceramic particles with different orientations as well as regions within the metallic cobalt binder close to the WC-Co interface.

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