The inhibition of recrystallization in high-strain nickel-based single-crystal superalloys remains a critical challenge for advanced turbine blade applications. This study investigates the evolution of the primary γ’ phase and dislocation during annealing in a third-generation Re-containing single-crystal superalloy (WZ30) subjected to 5% compressive deformation. Isochronal annealing (700 to 1200 °C, 1 min) combined with scanning electron microscopy (SEM) and an electron backscatter diffraction (EBSD) analysis revealed a nonlinear variation of the geometrically necessary dislocation (GND) density, which reached a minimum of 1000 °C with 62.7% of the primary γ’ phase retained. Prolonged recovery annealing at 1000 °C for 10 h effectively inhibited recrystallization during subsequent solution heat treatment. This result provides a practical strategy for inhibiting recrystallization in single-crystal superalloys.

The nanoscale Cu-rich precipitates (CRPs) are one of the most critical microstructural features responsible for degrading the mechanical properties of reactor pressure vessel (RPV) steels. The prospect of the rapid regeneration of the service performance of degraded materials through electropulsing is attractive, and electropulsing has been proven to have the application potential to eliminate the CRPs and recover the mechanical properties of RPV materials. However, few studies have investigated the secondary service issue of electropulsing. This paper provides experimental findings from microstructural investigations and property evaluations of a FeCu RPV model alloy subjected to re-aging following recovery electropulsing and annealing treatments. The evolution behavior of CRPs and the changes in the hardness of the alloy during the re-aging process after electropulsing treatment were consistent with the initial aging process, while the re-aging process of the annealing treatment group was quite different from the initial aging. The difference between the electropulsing and annealing treatment groups was that the annealing treatment failed to eliminate the precipitates completely, leaving behind some large precipitates. This work demonstrates the potential application of EPT in this field.

Nanoscale Cu-rich precipitates (CRPs) play a crucial role in the irradiation embrittlement of reactor pressure vessels (RPVs), and binary Fe-Cu alloys serve as practical models to study the evolution of these precipitates. This study investigates the electrical resistivity of an Fe-1.17 wt.% Cu model alloy aged at 450 °C to enhance the understanding of electrical measurements for the non-destructive assessment of RPV irradiation embrittlement. Multi-level characterization methods were used to obtain quantitative data on multi-scale microstructures, including precipitates, dislocations, and grains. The formation and growth of CRPs were found to align closely with the Johnson–Mehl–Avrami model, and the variation in electrical resistivity showed a strong correlation with the evolution of the microstructure. Combined with detailed quantitative microstructure evolution analysis, an electrical resistivity prediction model that considers microstructural mechanisms has been developed. This model can accurately show the effect of CRPs on resistivity and can potentially be extended to RPV steels with other solute-rich precipitates, with a maximum absolute percentage error not exceeding 5%. These results provide a robust basis for the non-destructive and in-service evaluation of RPV irradiation embrittlement using electrical resistivity.

Creep is one of the primary degradation mechanisms affecting the performance of the 800H alloy under long-term high-temperature stress conditions. Understanding the microstructural evolution during creep and developing a quantitative model to relate these changes to mechanical properties are essential for assessing creep damage and ensuring the safe operation of high-temperature equipment. By conducting a multiscale quantitative characterization of the microstructures in the 800H alloy across different creep stages, we systematically examined the evolution of various microstructural features and their influence on Young’s modulus. A quantitative prediction model of Young’s modulus based on microstructural characteristics was developed, achieving a prediction accuracy exceeding 95% with a mean absolute percentage error of just 1.59% compared to experimental values. This work not only elucidates the intrinsic relationship between microstructural features and macroscopic mechanical properties but also provides a foundation for the in-service creep damage assessment of high-temperature components.

Stereolithography (SL) based additive manufacturing technology facilitates fabricating structurally complicated silicon-based ceramic cores. However, SL fabricates ceramic component by layer-by-layer solidification of ceramic slurries. The instability of ceramic slurries often leads to the phenomenon of ceramic particle gradient distribution in the prepared ceramic component, which can damage the mechanical properties, porosity, and dimensional accuracy of ceramic component, hindering the application of SL in the preparation of ceramic component. Herein, we systematically investigated and optimized such impacting factors, including particle size distributions, addictive (nanopowder) and solid loading, which result in appropriate viscosity and high stability of SiO₂ ceramic slurries. A SiO₂ ceramic slurry for SL showed the viscosity (26.1 Pa·s) and after 264 h sedimentation time with 80 wt.% of solid loading. Using the slurry, we prepared a ceramic with a shrinkage rate maintained below 4%, a porosity of 21.56%, and a flexural strength of 20.53 MPa.

Difficult-to-machine metallic materials, distinguished by their high strength, hardness, and corrosion resistance, are indispensable in critical fields such as aerospace and defense. However, these very attributes also pose substantial challenges to conventional machining technologies. As an advanced external-field machining technology, electropulsing-assisted machining provides unique advantages in enhancing plastic deformability, refining microstructures, improving machining precision, and boosting efficiency. This paper provides a comprehensive review of the fundamental mechanisms governing the interaction between electropulsing and metallic materials, synthesizes the latest advances in electropulsing-assisted machining methods, and highlights unresolved challenges alongside promising future directions. By bridging the gap between material science and advanced manufacturing, this review aims to stimulate innovation and accelerate the adoption of electropulsing-assisted machining in the processing of next-generation high-performance metallic materials.