Chen Yuyang, Fu Yinzhi, Jia Xianshi, Li Kai, Wang Cong
State Key Laboratory of Precision Manufacturing for Extreme Service Performance, College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
Materials (Basel). 2025 Aug 15;18(16):3839. doi: 10.3390/ma18163839.
Ultrafast laser welding of glass/metal heterostructures has found extensive applications in sensors, medical devices, and optical systems. However, achieving high-stability, high-quality welds under non-optical contact conditions remains challenging due to severe internal damage within glass materials. This study addresses thermal management through synergistic control of thermal accumulation effects and material ablation thresholds. Using the sapphire/Invar alloy system as a model for glass/metal welding, we investigated thermal accumulation effects during ultrafast laser ablation of Invar alloy through theoretical simulations. Under a repetition rate of 1 MHz, the femtosecond laser raised the lattice equilibrium temperature by 700 K within 10 microseconds, demonstrating that high repetition rate femtosecond lasers can induce effective heat accumulation in Invar alloy. Furthermore, ablation thresholds for both materials were determined across varying repetition rates via the D method, with corresponding threshold curves systematically constructed. Finally, based on the simulation and ablation threshold calculation results, laser parameters were selected for ultrafast laser single point welding of sapphire and Invar alloy. The experimental results demonstrate effective thermal effect mitigation, achieving a maximum shear strength of 63.37 MPa. Comparative analysis against traditional scan welding further validates the superiority of our approach in thermal management. This work provides foundational theoretical and methodological guidance for ultrafast laser welding of glass/metal heterostructures.
玻璃/金属异质结构的超快激光焊接已在传感器、医疗设备和光学系统中得到广泛应用。然而，由于玻璃材料内部严重受损，在非光学接触条件下实现高稳定性、高质量的焊接仍然具有挑战性。本研究通过协同控制热积累效应和材料烧蚀阈值来解决热管理问题。以蓝宝石/殷钢合金体系作为玻璃/金属焊接的模型，我们通过理论模拟研究了殷钢合金超快激光烧蚀过程中的热积累效应。在1 MHz的重复频率下，飞秒激光在10微秒内将晶格平衡温度提高了700 K，表明高重复频率飞秒激光可在殷钢合金中诱导有效的热积累。此外，通过D方法在不同重复频率下确定了两种材料的烧蚀阈值，并系统地构建了相应的阈值曲线。最后，基于模拟和烧蚀阈值计算结果，选择激光参数对蓝宝石和殷钢合金进行超快激光单点焊接。实验结果表明热效应得到有效缓解，实现了63.37 MPa的最大剪切强度。与传统扫描焊接的对比分析进一步验证了我们方法在热管理方面的优越性。这项工作为玻璃/金属异质结构的超快激光焊接提供了基础理论和方法指导。
