Indentation in Materials Science: Advances in Theory, Instrumentation, and Multiscale Applications.

INTRODUCTION

This review systematically examines the advances in micro-nano indentation technology, an innovative method for cross-dimensional extraction of mechanical properties, which overcomes limitations of traditional testing techniques.

METHODS

The development of instrumentation and standardization is reviewed. Key theoretical models and analysis methods are discussed, including the Oliver-Pharr method, strain gradient plasticity, viscoelastic models, and the Laugier model for fracture toughness. Recent patent-related innovations in hardware, such as in-situ high-temperature/vacuum systems (e.g., CN112229752A, CN117129355A) and high-speed sampling technologies, are highlighted.

RESULTS

The indentation response across various material systems (metals, ceramics, biomaterials, composites, flexible electronics, 2D materials) is analyzed. Case studies demonstrate successful applications in industrial coating evaluation, revealing Hall-Petch relationship anomalies in nanocrystalline metals, and inspiring biomimetic material design.

DISCUSSION: Challenges like surface roughness effects and instrument response delay during highstrain- rate testing are addressed, alongside solutions involving surface pretreatment and novel noisereduction algorithms (e.g., patent CN202411212667.8).

CONCLUSION

Nanoindentation technology shows strong interdisciplinary potential. Future development should focus on in-situ multimodal systems, machine learning integration, standardization, and extreme environment testing, facilitating its transition from a characterization tool to a design platform. Relevant patented technologies play a crucial role in this evolution.