Extending nanoindentation testing toward extreme strain rates and temperatures for probing materials evolution at the nanoscale.

Abstract: For the past 30 years, nanoindentation has provided critical insights into the microstructure-strength relationship for a wide range of materials. However, it has traditionally been limited to quasistatic testing at room temperature, which has hindered a holistic understanding of microstructurally induced deformation mechanisms and their dynamic evolution as a function of the temperature and strain rate. Over the past decade, the operational scope of nanoindentation has expanded dramatically. Temperatures up to 1100°C and strain rates as high as 10⁺⁴ s^-1 and as low as 10^-8 s^-1 have become accessible. In addition, advanced techniques allow tracking microstructural evolution and corresponding changes in mechanical behavior during deformation under extreme conditions. These advancements have transformed nanoindentation into a versatile tool for comprehensive materials characterization, enabling high-throughput investigations under multimodal conditions.

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