The fast thermal and electromagnetic transients that occur in a superconducting magnet in case of a quench have the potential of generating large mechanical stresses both in the superconducting coils and in the magnet structure. While the investigation of such quench loads should generally be conducted to ensure a safe operation of the system, its importance is greatly enlarged in the case of high-field magnets based on strain sensitive superconductors. For these, a rigorous analysis of the magnet mechanics during a quench becomes critical. The scope of this work is hence to bring, for the first time, a detailed understanding of the three-dimensional mechanical behavior of a Nb₃Sn accelerator magnet during a quench discharge. The study relies on the use of finite element models, where various multi-domain simulations are employed together to solve the coupled physics of the problem. Our analysis elaborates on the case study of the new MQXF quadrupole magnet, currently being developed for the high-luminosity upgrade of the LHC. Notably, we could find a very good agreement between the results of the simulation and experimental data from full-scale magnet tests. The validated model confirms the appearance of new peak stresses in the superconducting coils. An increase in the most relevant transverse coil stresses of 20–40 MPa with respect to the values after magnet cool-down has been found for the examined case.

在失超的情况下，超导磁体中发生的快速热和电磁瞬变有可能在超导线圈和磁体结构中产生大的机械应力。虽然通常应进行此类失超负荷的调查以确保系统的安全运行，但在基于应变敏感超导体的高场磁体的情况下，其重要性大大增加。对于这些，在失超期间对磁体力学进行严格的分析变得至关重要。因此，这项工作的范围是首次详细了解 Nb _{3 的}三维力学行为。失超放电期间的 Sn 加速器磁铁。该研究依赖于有限元模型的使用，其中结合使用各种多域模拟来解决问题的耦合物理。我们的分析详细阐述了新型 MQXF 四极磁铁的案例研究，该磁铁目前正在为 LHC 的高亮度升级而开发。值得注意的是，我们可以发现模拟结果与全尺寸磁铁测试的实验数据之间非常吻合。经验证的模型证实了超导线圈中出现了新的峰值应力。对于所检查的情况，发现与磁铁冷却后的值相比，最相关的横向线圈应力增加了 20-40 兆帕。