Novel Correlations Between Process Forces and Void Morphology for Effective Detection and Minimization of Voids During Friction Stir Welding
Novel Correlations Between Process Forces and Void Morphology for Effective Detection and Minimization of Voids During Friction Stir Welding
复制标题
工艺力与空洞形态之间的新关联，可有效检测搅拌摩擦焊过程中的空洞并将其最小化
DOI：
10.1115/1.4054338
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Rudraraju, Shiva
中科院分区：
文献类型：
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作者：
Ansari, Mohammad Ali;Agiwal, Hemant;Zinn, Mike;Pfefferkorn, Frank;Rudraraju, Shiva
搅拌摩擦焊(FSW)过程中产生的亚表面空洞和材料异质性通常需要进行焊后检查，以确保通过这种固态焊接过程获得的焊缝质量。在这种情况下，过程中的空洞检测技术可能有助于优化工艺条件，从而减少昂贵且耗时的焊缝后处理检查。目前的过程中空洞检测技术依赖于试图将部分规模的焊接质量与空洞形成直接关联的方法，而不是对调节空洞演化的基本力学和材料物理有基本的了解。在这项工作中，我们展示了一种有效的过程中数值技术，该技术使用加工力信号来检测体积空洞的形成，并将力信号中的变化与工具探头和底层材料空洞之间的相互作用联系起来。我们的方法依赖于对FSW过程的高保真有限元分析模拟，以及通过数值获得的过程力信号与相应的空洞结构的关联。这种关联式是在将刀具上的面内反作用力与刀具旋转角度联系起来的相空间中得到的。我们重点研究了刀具几何形状和刀具运动与周围材料发生塑性变形时的相互作用，并对刀具运动和空洞形成的各种关系提出了新的见解。通过这种方法，我们可以确定可以优化的与工具相关的工艺条件，以最大限度地减少空洞的形成，并展示了一种潜在的基于力的就地空洞监测方法，该方法与FSW过程中的基本塑性流动和空洞结构相联系。
Sub-surface voids and material heterogeneities resulting from the friction stir welding (FSW) process often necessitate post-weld inspection to ensure the quality of weld obtained from this solid-state welding process. In this context, in-process void detection techniques can potentially help in optimizing the process conditions and thereby reduce expensive and time-consuming post-process inspection of welds. Current in-process void detection techniques rely on approaches that try to directly correlate the part-scale welding quality to void formation, without a fundamental understanding of the underlying mechanics and materials physics that modulate void evolution. In this work, we demonstrate an effective in-process numerical technique that uses process force signals to detect volumetric void formation and connect the variations in the force signals to interactions between the tool probe and the underlying material voids. Our approach relies on a high-fidelity finite element analysis simulation of the FSW process and on correlation of numerically obtained process force signals with the corresponding void structures. This correlation is obtained in the phase-space relating in-plane reaction forces on the tool to the tool rotation angle. We focus on the interactions of the tool geometry and tool motion with the surrounding material undergoing plastic deformation and deduce novel insights into various correlations of tool motion and void formation. Through this approach, we can identify tool-related process conditions that can be optimized to minimize void formation and demonstrate a potential in situ force-based void monitoring method that links to the underlying plastic flow and void structures during the FSW process.