PSI - Issue 56

Balichakra Mallikarjuna et al. / Procedia Structural Integrity 56 (2024) 184–189 Mallikarjuna / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 2. Predicted melt pool top and cross-sectional view while deposiiton of layer 2 and track 3 at constant velocity (V) = 15 mm/s and different laser power (a) and (b) 250 W; (c) and (d) 300 W; (d) and (e) 350 W (Mallikarjuna, 2020) Ǥ Fig.2. Shown the melt pool FE contours predicted for varying laser power at constant travel speed. The red colour in the melt pool contour indicates the molten region where the liquidus temperature is greater than the 1460 °C of the TiAl material. The melt pool length, width, and depth increased as the laser power was increased from 250 W to 350 W at a constant velocity of 15 mm/s. The melt pool length increased from 0.425 mm to 0.55 mm, while the depth increased from 0.1 to 0.29 mm, and the width increased from 0.412 to 0.5 mm. This increase in melt pool dimensions with the increase in laser power can be attributed to the higher energy available at increasing powers to melt the powder. However, melt pool size (length, width, and depth) decreased for varying travel speeds (10, 15, 20 mm/s) at a constant laser power of 300 W. This can be attributed to the fact that the powders were less exposed under the laser. 3.2 Thermal cycling during deposition of plate

Fig 3. (a) and (c) Peak thermal history in tracks and layers of the plate for P = 300 W, V = 15 mm/s and (b) and (d) Locations used to extract temperatures of respective tracks and layers (Mallikarjuna, 2020).