[论文解读] On the configurational force associated with blocked slip bands at grain boundaries in α-Ti

Abdalrhaman Koko|arXiv (Cornell University)|Mar 25, 2026

Microstructure and mechanical properties被引用 0

一句话总结

本论文将 configurational force 框架应用于 α-Ti 的 HR-EBSD 测量中的阻塞滑移带，以量化滑移带阻塞在晶界处的能量驱动力，将局部应力定位与相邻晶粒中的潜在扩展方向联系起来。

ABSTRACT

Grain boundaries can block slip-band propagation and generate intense local stress and strain fields that influence subsequent deformation and damage initiation in polycrystalline metals. Conventional geometric criteria, such as Schmid factor and slip-transfer parameters, describe crystallographic compatibility but do not quantify the energetic severity of a blocked slip event. Here, we apply a configurational force framework to high-angular-resolution electron backscatter diffraction (HR-EBSD) measurements obtained from a blocked slip band in commercially pure titanium. By evaluating a J-type equivalent domain integral from the measured elastic field, we quantify both the magnitude and directional dependence of the local energetic driving force associated with the stress localisation; thus, providing an energetic descriptor of the tendency for deformation to extend into the neighbouring grain. The results show a marked decoupling between conventional geometric metrics and the configurational force response, indicating that the local stress-localisation geometry strongly influences which crystallographically admissible extension directions in the neighbouring grain are energetically favoured. The framework provides a physically grounded basis for quantifying blocked-slip severity and for motivating future in situ studies aimed at defining a critical transfer threshold for transfer or cracking.

研究动机与目标

• 推动需要一种超越几何准则（如 Schmid 因子）的阻塞滑移事件能量描述符的必要性。
• 将 configurational force 框架应用于实验性 HR-EBSD 数据，以量化局部驱动力。
• 评估局部应力定位如何影响跨晶界能量上更有利的转移或断裂方向。

提出的方法

• 从测量的弹性场计算一个 J-type 等效域积分以获得构形力。
• 将商用级纯钛的阻塞滑移带 HR-EBSD 测量作为数据源。
• 分析与应力定位相关的局部能量驱动力的大小及方向依赖性。
• 将构形力结果与传统几何度量进行比较，以评估几何与能量学之间的耦合/解耦。

实验结果

研究问题

• RQ1 从弹性场推导的构形力是否可量化晶界处阻塞滑移事件的能量严重性？
• RQ2 局部应力定位如何影响相较于传统几何准则在邻近晶粒中能量上有利的扩展方向？
• RQ3 几何度量是否能可靠预测跨晶界滑移转移或断裂的能量倾向？

主要发现

• conventional geometric metrics 与 configurational force 响应之间存在显著解耦。
• 局部应力定位几何显著影响哪些晶体学上可接受的扩展方向在能量上更有利。
• 该框架为量化阻塞滑移的严重性并推动未来原位研究提供了基于物理的基础。