Functionally Graded Materials and Structures: Unified Approach by Optimal Design, Metal Additive Manufacturing, and...

Area of Science:

• Materials Science and Engineering
• Additive Manufacturing
• Computational Materials Design

Background:

• Functionally Graded Materials (FGMs) offer superior performance compared to homogeneous materials.
• Digitalization and additive manufacturing enable the creation of materials with tailored properties.
• Joining dissimilar metals for compositional grading remains an underexplored area with significant engineering potential.

Purpose of the Study:

• To propose a multidisciplinary methodology for creating structure-specific oriented FGM parts.
• To address the metallurgical challenges in joining dissimilar metals for FGMs.
• To develop a conceptual digital workflow for FGM design and manufacturing.

Main Methods:

• Utilizing topology optimization for FGM design.
• Employing multi-feed Wire-Arc Additive Manufacturing (WAAM) for synthesis.
• Integrating image-based characterization and numerical validation with full-field deformation data.
• Analytical validation of a layer-wise FGM concept using a beam under pure bending.

Main Results:

• A conceptual FGM engineering workflow was proposed, enabling digital data conversion for geometry and compositional grading.
• A case study of an optimized FGM beam (iron to copper gradient) demonstrated a 26% reduction in normal pure bending stresses.
• The study validates the digital workflow for in silico processing towards experimental production.

Conclusions:

• The proposed methodology offers a pathway for advanced FGM part fabrication.
• Digital tools and additive manufacturing are crucial for realizing complex material gradients.
• Further research can advance the experimental realization of FGMs based on this digital workflow.