An Innovative Method to Analyse the Geometrical Accuracy of Ti6Al4V Octet-Truss Lattice Structures

Area of Science:

• Additive Manufacturing
• Materials Science
• Mechanical Engineering

Background:

• Metal lattice structures offer high structural efficiency.
• Titanium alloy (Ti6Al4V) is increasingly used in additive manufacturing.
• Characterization of Ti6Al4V lattice structures produced by Electron Beam Melting (EBM) requires further investigation.

Purpose of the Study:

• To develop a measurement method for assessing the dimensional accuracy of Ti6Al4V octet truss lattice structures.
• To analyze the geometric differences between designed and manufactured Ti6Al4V lattice beams.
• To investigate the influence of build orientation on dimensional accuracy.

Main Methods:

• Analysis of beam specimens with a 2 mm diameter.
• Comparison of designed and manufactured beam geometries.
• Evaluation of beam specimens at different growth orientations relative to the build direction (0°, 45°, 90°).

Main Results:

• Electron Beam Melting (EBM) manufactured beams are generally thinner than designed.
• Beam cross-sections are nearly circular for orientations at 45° and 90°.
• The cross-section of horizontal beams (0° orientation) deviates significantly from circularity.

Conclusions:

• The study successfully developed a method to assess dimensional accuracy in EBM-produced Ti6Al4V lattices.
• Build orientation critically affects the dimensional accuracy and cross-sectional shape of Ti6Al4V lattice beams.
• Understanding these geometric deviations is crucial for optimizing the design and application of EBM-manufactured lattice structures.