再结晶作为表征和控制冷喷涂材料性能的工具：以316L钢为例
Recrystallization as a tool to characterize and control the properties of cold sprayed materials: case study on 316L steel
浏览论文内容
中文总结 AI 辅助
本研究以316L钢为例，通过EBSD和纳米压痕表征，揭示冷喷涂材料中变形诱导的异质性驱动再结晶，并证明可控再结晶可表征沉积变形并调控材料性能。
中文摘要 AI 辅助
由于独特的堆积机制，冷喷涂材料中的再结晶行为与传统材料显著不同。本研究利用EBSD和纳米压痕技术，探讨了冷喷涂材料中变形诱导的微观结构异质性、再结晶行为与力学性能之间的关系。选用316L不锈钢作为模型材料。对沉积态样品以及经900至1100 K温度退火后的样品进行了表征。热力学估算表明，在冲击过程中，颗粒界面局部温度可升至1000 K以上，并形成极高的位错密度（高达10^17 m^-2），为后续再结晶提供了强大的驱动力。EBSD观察证实了颗粒界面附近存在强烈的缺陷积累和晶粒碎化。在1000 K退火后，再结晶优先在这些高应变区域开始，并随温度和保温时间的增加而推进，在1100 K保温1小时后实现完全再结晶。再结晶晶粒尺寸分布符合重尾对数正态分布，表明颗粒冲击过程中产生了极不均匀的应变分配。纳米压痕测量显示，冷喷涂沉积物的高硬度在900 K退火后基本保持不变，但随着再结晶的进行逐渐降低。我们进一步证明，可控的喷涂后再结晶可作为表征沉积过程中变形以及调控冷喷涂材料微观结构和力学性能的有力工具。
英文摘要
Owing to the unique buildup mechanisms, recrystallization in cold sprayed materials significantly differs from that in conventional counterparts. In this study, the relationship between deformation-induced microstructural heterogeneity, recrystallization behavior, and mechanical properties of cold sprayed materials was investigated using EBSD and nanoindentation. The 316L stainless steel was selected as a model material. The deposit was characterized in its as-sprayed condition and after annealing at temperatures between 900 and 1100 K. Thermomechanical estimates suggest that locally, temperature can rise over 1000 K and very high dislocation densities (up to 1017 m-2) form at particle boundaries during impact, providing a strong driving force for subsequent recrystallization. The EBSD observations confirmed the intense defect accumulation and grain fragmentation localized near the particle interfaces. Recrystallization initiated preferentially in these highly strained areas after annealing at 1000 K and progressed with increasing temperature and holding time, leading to complete recrystallization after 1 h at 1100 K. The recrystallized grain-size distribution was well described by a heavy-tailed log-normal distribution, which indicates extremely heterogeneous strain partitioning generated during particle impacts. Nanoindentation measurements showed that the high hardness of the cold sprayed deposit remained largely unchanged after annealing at 900 K but gradually decreased as recrystallization progressed. We further demonstrate that controlled post-spray recrystallization can serve as a powerful tool for characterizing deformation during deposition and for tailoring the microstructure and mechanical properties of cold-sprayed materials.
发表机构
- Czech Technical University in Prague（布拉格捷克理工大学）
- Institute of Plasma Physics of the Czech Academy of Sciences（捷克科学院等离子体物理研究所）
机构由 AI 辅助整理，请以论文原文为准。
