Mechanisms of vapour plume formation in laser deep penetration welding

Neural network of plume and spatter for monitoring high-power disk laser welding

“…Table 1 shows the testing results of NN with different s (s = 5, 6, 7) and different laser powers. (8) (9) Fig. 9 gives the neural network testing error curves which corresponds to laser powers 2 kW, 4 kW, 6 kW, 8 kW and 10 kW.…”

“…7 During deep penetration laser welding, high speed imaging was used to analyze the mechanisms of laser-induced plume. 8 The plasma plume optical radiation emitted during CO 2 laser welding of stainless steel samples was detected with a photodiode and analyzed under different process conditions. The discrete wavelet transform (DWT) could be used to decompose the optical signal into various discrete series of sequences over different frequency bands.…”

Laser wobble welding of fluid-based cooling channel joining for battery thermal management

“…Additionally, the laser wobbling/oscillation technique is suitable for joining highly reflecting and conducting materials used in battery connections as well as for producing structural seam weld. Laser welding is an attractive process to industry due to its ease of automation, high processing speed, high repeatability and cost-effective process [6,7].…”

Heat treatment of welded joints of steel 0.3С–1Cr–1Si produced by high-power fiber lasers

“…This steel is a widely used construction material, which is well-quenched and has limited weldability [16,17]. The basic defects in electric arc welding of these steels are hot and cold cracks, they are formed as a result of polymorphic and phase transformations (Austenite-Martensite, Austenite-FerriteþCementite, AusteniteBainite) [1][2][3][4][5][6][7][8][16][17][18][19][20][21] due to the change of volume, at high speeds of cooling after the thermal influence of welding. To reduce the cooling rate of the welded joint, pre-heating and related heating [22], postweld heat treatment [23][24][25][26][27][28][29] are used, besides it is necessary to prevent cooling of the welded joint to the room temperature.…”

“…Laser welding is used for welding of austenitic steels of various classes [2,8], duplex [6,9], zinc-coated [10], microalloyed [30] steels, and a large number of works is devoted to hybrid welding with various technological methods for welding of thick stock materials [4,[8][9][10].…”