Advances in phase identification and microstructural characterization of cement-based materials by nano-scratch technique

As an emerging micro-mechanical characterization technique, nano-scratch testing has recently gained significant attention in the study of cement-based materials. Compared with conventional micro-characterization methods, this technique applies a controlled load to the indenter that continuously scratches the material surface. By analyzing the resulting surface damage and deformation, it enables the quantitative determination of micromechanical properties such as scratch hardness, friction coefficient, and fracture toughness. Owing to its advantages of continuity, high precision, and high sensitivity, nano-scratch testing can effectively reveal the phase mechanical characteristics and microstructural properties of cement-based materials. This paper presents a comprehensive review of recent advances in the application of the nano-scratch technique for phase identification, interfacial transition zone (ITZ) analysis, and microscale mechanical characterization of cement-based materials. Furthermore, the limitations and challenges associated with its current applications are discussed. Finally, future directions for the development and innovative application of the nano-scratch testing in the field of cement-based materials are proposed, aiming to provide reference for both fundamental research and practical applications.