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Updated: Jun 5, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Meta-structure of amorphous-inspired 65.1Co28.2Cr5.3Mo lattices augmented by artificial intelligence.
Seong Je Park1, Woongbeom Heogh2, Jeongho Yang3
1School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798 Singapore.
Advanced Composites and Hybrid Materials
|December 11, 2024
Summary
Researchers additively manufactured a cobalt-chromium-molybdenum (CoCrMo) alloy lattice with an amorphous-inspired structure. This novel lattice exhibits high specific compression strength, enhanced by heat treatment and nanovesicle formation for advanced applications.
Area of Science:
- Materials Science
- Additive Manufacturing
- Biomaterials Engineering
Background:
- Additive manufacturing enables complex lattice structures with tailored properties.
- Cobalt-chromium-molybdenum (CoCrMo) alloys are widely used in biomedical and industrial applications due to their excellent mechanical properties and corrosion resistance.
- Controlling microstructure and phase distribution is crucial for optimizing the performance of additively manufactured alloys.
Purpose of the Study:
- To investigate the additive manufacturing of a CoCrMo alloy lattice with amorphous-inspired structures.
- To analyze the structure-property relationships, including specific compression strength and microstructural evolution.
- To explore post-processing techniques for enhancing mechanical performance and surface characteristics for advanced applications.
Main Methods:
- Laser powder bed fusion (LPBF) was employed to fabricate CoCrMo lattices with controlled hatching distances and periodic/aperiodic arrangements.
- Artificial intelligence (AI) was utilized for lattice alignment and design optimization.
- Microstructural characterization (equiaxial vs. columnar grains) and mechanical testing (compression strength) were performed.
- Solid-solution heat treatment and electrochemical leaching were applied for phase homogenization and surface modification (nanovesicles).
Main Results:
- The additively manufactured CoCrMo lattice exhibited an amorphous-inspired structure with high specific compression strength, approaching that of solid structures.
- Microstructural analysis revealed heterogeneous phase distribution (equiaxial nodes, columnar struts), impacting strength.
- Solid-solution heat treatment led to a homogeneous phase, significantly enhancing specific compression strength.
- Electrochemical leaching created nanovesicles, increasing surface area and enabling stress dissipation.
Conclusions:
- Additive manufacturing of CoCrMo lattices with controlled structures offers a pathway to high-performance materials.
- Microstructure and phase homogeneity are critical factors for maximizing mechanical strength in these lattices.
- Surface modification via nanovesicle formation presents opportunities for advanced functional designs, such as improved valve cages.
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