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Novel high speed nanoindentation data is reported for 0% and 100% state of charge (SoC) for the spinal LixMn2O4 material. The article also includes the load/displacement data for different SoC highlighting the displacement bursts corresponding to the pillar splitting for fracture toughness evaluation. For more details, please see the article; Mughal et al. (2016) [1]. Keywords: Fracture toughness, Pillar, Lithium ion battery, Nanoindentation, State of charge

Cementitious materials represent the most used materials in the construction industry. Their strong heterogeneity and multiscale microstructure make the study of the mechanical properties and the in-service behaviour very challenging: new techniques are required by industrial research to better investigate these aspects. In this work a novel technique based on statistical nanoindentation is exploited to obtain results about the microstructure build-up and the mechanical properties. An innovative high-speed nanoindentation method is here combined and compared with a standard nanoindentation procedure in order to get highly consistent statistical results. Combining the high-speed nanoindentation, the statistical deconvolution and SEM/EDS investigations, the main phases present in the tested hydrated cement paste have been characterized. High-resolution maps of the mechanical properties are in good agreement with SEM-EDS results. The evolution of the mechanical properties has been tested over the time and in particular after 1, 3, 5, 7, 14 and 28 days of hydration. It was found that the nano-mechanical properties were almost constant during the hydration time and the evolution of the bulk mechanical resistance properties of the cement paste is found to be due to a variation of the volume proportions between the three principal phases (low-density, high-density and ultra-high-density C–S–H). Keywords: Cement, Nanoindentation, High-speed, Statistical, Mapping, Packing density

This paper studies how the nano-mecha nical properties of thermal barrier coatings (TBCs) vary during thermal cy- cling, as a way to shed new light on their failure mechanisms. In particular, high-throughput nanoindentation re- vealed the evolution of hardness and elastic modulus distributions of plasma-sprayed yttria-stabilized zirconia (YSZ) top layers. The evolution of fracture toughness of the YSZ layers and the thermally grown oxide (TGO) formed onto the vacuum plasma-sprayed NiCoCrAlY bond coat were investigated by nanoindentation micro-pillar splitting. The TGO fracture toughness increases up to≈2.5–3.5 MPa√m at the early stages of thermal cycling, followed by a rapiddecrease to ≈2.0 MPa√m after a critical TGO thickness of ≈5μm isreached. Consequently, interface damage is initially limited to short cracks within the YSZ material. As TGO thickness exceeds the critical threshold, multiple cracks originate within the TGO and join through the YSZ to form long delamination cracks. Joining is favoured by a simultaneous loss in YSZ strength, testified by a decrease in the nanomechanical properties (hardness, elastic modulus) of both high- and low-porosity top coats. This is due to microstructural changes occurringbecause of the continuous interplay between sintering and thermal shock cracking in the YSZ layers. © 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/).