Abstract：In recent years, the service environments of railway, aerospace and nuclear equipment have become increasingly extreme with insufficient safety margin, leading to an increasing risk of failure in critical loading components. Developed countries, such as America and Europe, are actively promoting the fundamental and significant role of nondestructively in situ experimental technology in material internal damage characterization. Among these efforts, the cross-scale or full-field modeling of quantitative defect-life correlation has emerged as a common technical challenge for the long-term safety service of advanced equipment under extreme environment. Therefore, this paper, driven by the urgent demand for internal mechanical full-field measurement of the materials and structures, specially addresses the technical challenges faced in the cross-scale assessment of internal damage evolution typically under ultra-high temperature, ultra-low temperature, strong corrosion, and high impact, etc. To tackle this issue, this paper briefly reviews the recent progress and challenge of extreme mechanical testing devices primarily based on high-resolution X-ray imaging and their typical engineering applications and recent progress, specially highlighting the urgency, challenges, and cutting-edge nature of this direction in the community of solid mechanics and engineering science. The deep understanding and potential scenarios of extreme mechanics can assist the rapid development of advanced structural materials, significantly enhancing the capability of bridging the service performance of key equipment and engineering facility from the viewpoints of multiple fields and scales. Such achievement can promote the design capacity of new materials and structures.
2026, Vol. 47 
