• Chinese Optics Letters
  • Vol. 23, Issue 3, 031201 (2025)
Guanming Xie1,2, Weixin Ma1,2, Yueqiang Zhang1,2,*, Sanhong Wang3..., You Li4, Biao Hu1,2, Shaohua Yan1,2, Yu Fu1,2 and Qifeng Yu1,2,5|Show fewer author(s)
Author Affiliations
  • 1Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection, Shenzhen University, Shenzhen 518060, China
  • 2College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
  • 3Shenzhen Sincevision Technology Co., Ltd., Shenzhen 518055, China
  • 4National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing 100094, China
  • 5College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China
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    DOI: 10.3788/COL202523.031201 Cite this Article Set citation alerts
    Guanming Xie, Weixin Ma, Yueqiang Zhang, Sanhong Wang, You Li, Biao Hu, Shaohua Yan, Yu Fu, Qifeng Yu, "Keyhole morphology monitoring in laser welding using optical coherence tomography," Chin. Opt. Lett. 23, 031201 (2025) Copy Citation Text show less
    Schematic of the keyhole monitoring system.
    Fig. 1. Schematic of the keyhole monitoring system.
    Experimental setup of the keyhole monitoring system.
    Fig. 2. Experimental setup of the keyhole monitoring system.
    Keyhole morphology on (a)–(d) 304 stainless steel and (e)–(h) 6061 Al alloy. The welding speeds are (a), (e) 10, (b), (f) 25, (c), (g) 50, and (d), (h) 100 mm/s, respectively.
    Fig. 3. Keyhole morphology on (a)–(d) 304 stainless steel and (e)–(h) 6061 Al alloy. The welding speeds are (a), (e) 10, (b), (f) 25, (c), (g) 50, and (d), (h) 100 mm/s, respectively.
    Seam surface macrograph and weld cross-section micrograph of (a) 304 stainless steel and (b) 6061 Al alloy.
    Fig. 4. Seam surface macrograph and weld cross-section micrograph of (a) 304 stainless steel and (b) 6061 Al alloy.
    Surface views of keyhole morphology on 304 stainless steel at (a) 10 and (b) 100 mm/s; 6061 Al alloy at (c) 10 and (d) 100 mm/s. The processing beam center is marked by the crosshairs, and the processing beam diameter is represented by the red circle. The white regions represent no signal.
    Fig. 5. Surface views of keyhole morphology on 304 stainless steel at (a) 10 and (b) 100 mm/s; 6061 Al alloy at (c) 10 and (d) 100 mm/s. The processing beam center is marked by the crosshairs, and the processing beam diameter is represented by the red circle. The white regions represent no signal.
    Longitudinal views of keyhole morphology on (a)–(d) 304 stainless steel and (e)–(h) 6061 Al alloy. The welding speeds are (a), (e) 10, (b), (f) 25, (c), (g) 50, and (d), (h) 100 mm/s, respectively. The processing beam center is marked by the black lines, and the processing beam diameter is represented by the red dotted lines. The welding direction is from left to right.
    Fig. 6. Longitudinal views of keyhole morphology on (a)–(d) 304 stainless steel and (e)–(h) 6061 Al alloy. The welding speeds are (a), (e) 10, (b), (f) 25, (c), (g) 50, and (d), (h) 100 mm/s, respectively. The processing beam center is marked by the black lines, and the processing beam diameter is represented by the red dotted lines. The welding direction is from left to right.
    Keyhole lag for 304 stainless steel and 6061 Al alloy with different welding speeds.
    Fig. 7. Keyhole lag for 304 stainless steel and 6061 Al alloy with different welding speeds.
    MaterialChemical composition
    304CrNiMnSiBSCPFe
    Mass fraction (%)18.188.481.750.570.100.030.050.03Bal.
    6061MgFeCuMnSiZnCrNiAl
    Mass fraction (%)1.000.700.280.150.600.250.200.05Bal.
    Table 1. Compositions of 304 Stainless Steel and 6061 Al Alloy
    MaterialPower (W)Defocus (mm)P/d (kW/mm)Speed (mm/s)Scan size (μm × μm)Data points
    3046000310, 25, 50, 100550 × 550200 × 200
    606112000610, 25, 50, 100550 × 550200 × 200
    Table 2. Process Parameters
    Guanming Xie, Weixin Ma, Yueqiang Zhang, Sanhong Wang, You Li, Biao Hu, Shaohua Yan, Yu Fu, Qifeng Yu, "Keyhole morphology monitoring in laser welding using optical coherence tomography," Chin. Opt. Lett. 23, 031201 (2025)
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