STTR Phase I: Laser Ultrasonic Emission Sensor for In-process Monitoring during High-Speed Laser Welding

小企业技术转让研究（STTR）第一阶段项目将证明在高速激光焊接薄板过程中监测焊接质量的技术可行性，这对制造燃料电池至关重要。该监测系统基于激光检测焊接过程中发出的微小超声波信号。所提出的技术是基于激光的超声检测的修改。在这项技术中，高速激光焊接过程被用作超声波源和激光干涉仪被用来连续监测在焊接池产生的超声波发射，并评估焊接质量。拟议的激光焊接过程中的监测技术是至关重要的商业氢燃料电池的制造中使用的下一代能源效率的运输车辆。新的过程中监测技术将允许实时监测焊接质量，抑制对后处理检查的需求。其他广泛使用激光焊接薄零件的行业，如制药行业，可以从拟议的过程中传感器中受益。

The Small Business Technology Transfer Research (STTR) Phase I project will demonstrate the technical feasibility for in-process monitoring of welding quality during high-speed laser welding of thin plates which is critical to manufacturing of fuel cells. The monitoring system is based on laser detection of small ultrasonic signals emitted during the welding process. The proposed technique is a modification of laser-based ultrasonic inspection. In this technique, the high-speed laser welding process is used as the ultrasonic source and a laser interferometer is used to continuously monitor the ultrasonic emission generated at the weld pool and to assess the weld quality. The proposed in-process laser welding monitoring technique is critical for the manufacturing of commercial hydrogen fuel cells to be used in the next generation of energy efficient transportation vehicles. The new in-process monitoring technique will allow to monitor weld quality in real-time, suppressing the need for post-process inspection. Other industries where laser welding of thin parts is intensively used, such as the pharmaceutical industry, could benefit from the proposed in-process sensor.