Trigonometric gradient microstructures in additively manufactured single crystals enable strength-ductility synergy...

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Additively manufactured (AM) single crystals (SXs) are promising for extreme environments.
• AM processes create unique gradient microstructures around dendrites, affecting material properties.
• Understanding and controlling these microstructures is key to enhancing performance.

Purpose of the Study:

• To develop a unified model for gradient microstructures in AM SXs.
• To quantify the impact of these microstructures on mechanical properties.
• To enable programmable performance by tuning microstructural gradients.

Main Methods:

• Leveraging a unified trigonometric function to describe gradient microstructures.
• Analyzing dislocation densities, matrix channel width, precipitate area, and elemental concentrations.
• Employing high-throughput simulations to correlate microstructure intensity with mechanical properties.

Main Results:

• Trigonometric gradient microstructures (TGMs) overcome the strength-ductility trade-off, particularly at elevated temperatures.
• TGMs improve both strength and ductility, unlike conventional methods that sacrifice ductility for strength.
• Linear correlations were found between TGM intensity and mechanical properties like strength and elongation.

Conclusions:

• TGMs offer a novel approach to tailor mechanical properties in AM SXs.
• The study provides a framework for designing materials with programmable performance for demanding applications.
• This research deepens the understanding of dendrite-related microstructures in AM alloys.