Study of the Compression Behaviour of Ti6Al4V Trabecular Structures Produced by Additive Laser Manufacturing

Area of Science:

• Materials Science
• Mechanical Engineering
• Biomedical Engineering

Background:

• Additive laser manufacturing enables the creation of complex lattice structures with tailored mechanical properties.
• Trabecular bone structures are known for their high strength-to-weight ratio, inspiring engineered designs.

Purpose of the Study:

• To investigate the compression properties of additively manufactured Ti6Al4V trabecular structures.
• To correlate stiffness and yield strength with relative density using the Gibson and Ashby model.
• To compare the mechanical performance of different unit cell designs, including bending-dominated and stretching-dominated structures.

Main Methods:

• Fabrication of Ti6Al4V (titanium alloy) samples using additive laser manufacturing.
• Characterization of various lattice structures with different densities and unit cells.
• Compression testing to evaluate stiffness and yield strength.
• Analysis using the Gibson and Ashby model to relate properties to relative density.

Main Results:

• Stiffness and yield strength varied significantly between stretching-dominated (cubic) and bending-dominated (cross) structures at constant porosity.
• Cross structures exhibited the highest strength at a given stiffness due to favorable strut orientation.
• Deformation of structures generally did not substantially alter properties, except for the cubic structure where distortion increased bending and reduced strength.

Conclusions:

• The orientation and deformation mode of unit cells critically influence the mechanical properties of additively manufactured Ti6Al4V lattice structures.
• Bending-dominated designs, like cross structures, offer superior strength-to-stiffness performance.
• Understanding these relationships is crucial for designing optimized implants and structures for biomedical and engineering applications.