Metal 3D Printing of Low-NOx Fuel Injectors with Integrated Temperature Sensors Torres, J., 1,3 Mireles, J., 1,3 Chowdhury, A., 1,2 Wicker, R., 1,3 Choudhuri, A., 1,2 1 Department of Mechanical Engineering, The University of Texas at El Paso 2 Center for Space Exploration and Technology Research, The University of Texas at El Paso 3 W.M. Keck Center for 3D Innovation, The University of Texas at El Paso Process Characterization: Objective : • To utilize additive manufacturing for the fabrication of seamless low-NOx fuel injectors with integrated temperature measurement capabilities. Electron Beam Melting: Results Future Work Methodology & Materials Introduction Powder removal methodologies: Powder removal demonstration : The authors acknowledge the financial support for this work by the DOE - National Energy Technology Laboratory. Award Number:DE-FE0026330. Acknowledgements Student Involvement • Evaluate other powder removal methods including process parameter variations. • Begin the re-design and fabrication of a Low-NOx fuel injector given design constraints. Takeaways: Process characterization: Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Task 1: Development of design methodologies for EBM Fabrication of test parts for technology evaluation Evaluation of test parts Re-design for AM of Low-NOx fuel injector Alternative designs for sensor integration Task 2: Development of powder removal techniques Powder removal for internal channels Powder removal for internal cavities Process parameter modifications for optimal powder sintering Task 3: Testing of EBM-fabricated fuel injectors Functionality assessment of EBM-fabricated fuel injector Year 1 Year 2 Year 3 Letter Feature Factor Tested A Square base Dimensional accuracy B Lateral ridges (+) C Lateral ridges (-) D Descending cylinders (-) E Descending cylinders (+) F Staircase (-) G Staircase (+) H Cylinders (-) I Cylinders (+) J Ramps Surface roughness K Rectangular prisms Linear displacement error L Tensile bar Ultimate tensile strength EBM part fabrication: Test parts fabricated from different machine models a) A2X, b) A3, c) S12 a) b) c) Test parts fabricated for powder removal demonstration, each containing different sized output channels (1mm - 6mm) Measurement setup Process characterization: • Features smaller than 2.5 mm become deformed and the fabricated part measured larger than the intended geometry. • Features larger than 2.5 mm are very close to the intended geometry. • Walls tend to be thicker than the intended geometry, which may be due to surface roughness due to powder size. Powder removal: • Powder removal did not progress after 10 minutes of removing powder using the machine’s powder removal station. • Ultrasonic powder removal method is currently under further evaluation. 13 13.5 14 14.5 15 15.5 16 16.5 17 17.5 18 1 mm hole 2 mm hole 4 mm hole 6 mm hole Weight (grams) 19mm Cylinder Weight Initial Weight (+2 min) Weight (+2 min) Weight (+2 min) Weight (+2 min) 126 127 128 129 130 131 132 133 134 135 1 mm hole 2mm hole 4 mm hole 6 mm hole Weight (grams) 35mm Cylinder Weight Initial Weight (+2 min) Weight (+2 min) Weight (+2 min) Weight (+2 min) Weight (+2 min) 38 39 40 41 42 43 44 45 46 47 1 mm hole 2 mm hole 4 mm hole 6 mm hole Weight (grams) 25mm Cylinder Weight Initial Weight (+2 min) Weight (+2 min) Weight (+2 min) Weight (+2 min) Weight (+2 min) 0 5 10 15 20 Arcam A2 Arcam A2x Arcam S12 Dimensional deviation (mm) Dimensional Deviation vs. Machine Model 0 0.5 1 1.5 2 2.5 3 3.5 4 D1* D2 D3 D4 D5 D6 D7 Diameter (mm) Cylindrical Boss Diameter Original Arcam A2 Arcam A2x Arcam S12 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 E1 E2 E3 E4 E5 E6 E7** Diameter (mm) Cylinder Hole Diameter Original Arcam A2 Arcam A2x Arcam S12 0 5 10 15 20 25 30 35 Arcam A2 Arcam A2x Arcam S12 Surface Roughness (Ra) Surface Roughness (45° ramp) 0 5 10 15 20 25 30 Arcam A2 Arcam A2x Arcam S12 Surface Roughness (Ra) Surface Roughness (10° ramp) 289 289.5 290 290.5 291 291.5 292 292.5 293 293.5 294 294.5 1 mm hole 2 mm hole 4 mm hole 6 mm hole Weight (grams) 45mm Cylinder Weight Initial Weight (+2 min) Weight (+2 min) Weight (+2 min) Weight (+2 min)