Blog

How to reduce porosity in 3D printed titanium alloys through process optimization

To reduce porosity in 3D-printed titanium alloys through process optimization, consider the following strategies:
• Powder Packing Density: Increase the powder packing density to minimize porosity within the formed parts.
• Parameter Adjustment: Optimize parameters during the printing process, such as increasing laser power and reducing beam movement speed, to eliminate fusion defects.
• Protective Gases: Use optimized mixed protective gases like argon-helium mixtures to reduce spatter and defects, improving surface quality and reducing porosity.
• Temperature Control: Adjust and monitor the 3D printer's temperature to reduce the gases produced by the filament. For FDM (Fused Deposition Modeling), gradually decrease the printing temperature in increments of 5°C, while avoiding temperatures so low that they cause under-extrusion. Note that optimal printing temperatures vary depending on the filament material; PLA typically prints between 190°C and 220°C, ABS between 230°C and 260°C, and PETG between 210°C and 250°C.
• Filament Diameter Calibration: Calibrate the flow rate based on the filament's precise diameter; use digital calipers to measure the diameter at multiple points, calculate the average, and input this value into the slicing software.
• Preheating and Controlled Cooling: Preheating the material before laser melting, followed by maintaining insulation and slow cooling after forming, helps release residual stress and suppress crack formation.
• Atmosphere Control: Employ a controlled environment, such as a sealed chamber with argon gas, to minimize oxidation during processing.
• Unit Cell Shape Adjustment: Optimize the design of unit cell shapes to improve fatigue performance. Adjusting the unit cell shape is an effective method for improving fatigue performance.
• Proper Ventilation: Ensure adequate ventilation and air circulation around the 3D printer to minimize the accumulation of gases.
• Enclosure: Use a 3D printer enclosure to help contain fumes and keep them away from individuals in the area.
It's worth noting that the selection of specific techniques should align with the 3D printing method used, such as Selective Laser Melting (SLM) or Selective Electron Beam Melting (SEBM), and the intended application of the material.