Optical coherence tomography(OCT)offers a direct and precise measurement of keyhole depth in laser welding,facilitating its application for quality assurance and control.Nevertheless,in high-speed welding,the keyhole ...Optical coherence tomography(OCT)offers a direct and precise measurement of keyhole depth in laser welding,facilitating its application for quality assurance and control.Nevertheless,in high-speed welding,the keyhole lags behind the processing beam,leading to a reduction in OCT measurement accuracy.In this paper,OCT is utilized to monitor keyhole morphology by employing a scanner to deflect the measuring beam and the keyhole lag is quantitatively analyzed.Bead-on-plate welds were conducted on stainless steel and aluminum alloys at varying welding speeds.Real-time OCT data collection was performed and reconstructed to generate keyhole morphology.The aluminum alloy exhibited fluctuating keyhole morphology and irregular seam surfaces.The determination of the keyhole lag was based on the longitudinal view of keyhole morphology.Results indicated a proportional increase in keyhole lag with welding speed,and this trend was consistent for both materials.展开更多
Luminescent materials convert various types of energy (e.g.,light radiation, electromagnetic radiation/electric field, and mechanical stimulus) into light emissions, resulting in a multitude of luminescence processes ...Luminescent materials convert various types of energy (e.g.,light radiation, electromagnetic radiation/electric field, and mechanical stimulus) into light emissions, resulting in a multitude of luminescence processes called photoluminescence (PL), electroluminescence (EL), and mechanoluminescence (ML)(Table S1 online). Due to the intriguing photophysical properties of these luminescent materials, they are widely developed and applied in many fields such as information security, energy harvesting, light sources and displays, infrastructure health monitoring, electronics.展开更多
Optical coherence tomography(OCT)allows a direct and precise measurement of laser welding depth by coaxially measuring the keyhole depth and can be used for process monitoring and control.When OCT measurement was take...Optical coherence tomography(OCT)allows a direct and precise measurement of laser welding depth by coaxially measuring the keyhole depth and can be used for process monitoring and control.When OCT measurement was taken during single-beam laser welding,the keyhole instability of aluminum welding resulted in highly scattered OCT data and complicated the welding depth extraction methods.As a combination of an inner core beam and an outer ring beam,a novel adjustable ring mode(ARM)laser for producing a stable keyhole was applied to the OCT measurement.Different ARM laser power arrangements were conducted on aluminum and copper.The results indicated that the ring beam greatly improved the stability of the core beam-induced keyhole,and smooth welding depth can be extracted from the concentrated OCT data.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12372184 and 12002215)the Research Team Cultivation Program of Shenzhen University(No.2023JCT003)the National Key Research and Development Program of China(No.2019YFC1511102).
文摘Optical coherence tomography(OCT)offers a direct and precise measurement of keyhole depth in laser welding,facilitating its application for quality assurance and control.Nevertheless,in high-speed welding,the keyhole lags behind the processing beam,leading to a reduction in OCT measurement accuracy.In this paper,OCT is utilized to monitor keyhole morphology by employing a scanner to deflect the measuring beam and the keyhole lag is quantitatively analyzed.Bead-on-plate welds were conducted on stainless steel and aluminum alloys at varying welding speeds.Real-time OCT data collection was performed and reconstructed to generate keyhole morphology.The aluminum alloy exhibited fluctuating keyhole morphology and irregular seam surfaces.The determination of the keyhole lag was based on the longitudinal view of keyhole morphology.Results indicated a proportional increase in keyhole lag with welding speed,and this trend was consistent for both materials.
基金supported by the National Natural Science Foundation of China (61875136, 62275170, and 52002246)the Guangdong Provincial Science Fund for Distinguished Young Scholars (2022B1515020054)+2 种基金Science and Technology Innovation Commission of Shenzhen (JCYJ20200109105413475)Scientific Research Foundation as Phase II construction of high-level University for the Youth Scholars of Shenzhen University 2019 (000002110223)the support of Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection, Shenzhen University。
文摘Luminescent materials convert various types of energy (e.g.,light radiation, electromagnetic radiation/electric field, and mechanical stimulus) into light emissions, resulting in a multitude of luminescence processes called photoluminescence (PL), electroluminescence (EL), and mechanoluminescence (ML)(Table S1 online). Due to the intriguing photophysical properties of these luminescent materials, they are widely developed and applied in many fields such as information security, energy harvesting, light sources and displays, infrastructure health monitoring, electronics.
基金supported by the National Natural Science Foundation of China(No.12002215)the China Postdoctoral Science Foundation(No.2022T150437)the National Key Research and Development Program of China(No.2019YFC1511102)。
文摘Optical coherence tomography(OCT)allows a direct and precise measurement of laser welding depth by coaxially measuring the keyhole depth and can be used for process monitoring and control.When OCT measurement was taken during single-beam laser welding,the keyhole instability of aluminum welding resulted in highly scattered OCT data and complicated the welding depth extraction methods.As a combination of an inner core beam and an outer ring beam,a novel adjustable ring mode(ARM)laser for producing a stable keyhole was applied to the OCT measurement.Different ARM laser power arrangements were conducted on aluminum and copper.The results indicated that the ring beam greatly improved the stability of the core beam-induced keyhole,and smooth welding depth can be extracted from the concentrated OCT data.
