Breaking immiscibility barriers: ultrafast sintering of interlocked Cu-Fe-based composites

Area of Science:

• Materials Science
• Metallurgy
• Composite Materials

Background:

• Stringent application environments demand advanced structural materials.
• Conventional methods face challenges in producing uniform positive mixing enthalpy alloys due to segregation.
• Need for improved fabrication techniques to control microstructure and properties.

Purpose of the Study:

• To develop a novel bottom-up approach for fabricating Cu-FeCrMoB-C positive mixing enthalpy composites.
• To overcome limitations of conventional methods in controlling phase distribution and preventing segregation.
• To enhance mechanical properties such as tensile strength, wear resistance, and hardness.

Main Methods:

• Utilized ultrafast high-temperature sintering and instantaneous quenching for composite fabrication.
• Incorporated metallic glass particles as hard phase additives.
• Controlled size and distribution of phases by preventing liquid segregation during molten state.

Main Results:

• Achieved a uniform microstructure with precise control over phase size and distribution.
• Formed a robust interlocking structure between pure copper and composite phases.
• Resulting composite exhibited ~8x greater tensile strength, 40-50x improved wear resistance, and 10x increased Vickers hardness compared to pure copper.
• Mitigated elemental cross-diffusion and phase separation through rapid quenching.

Conclusions:

• The innovative sintering and quenching method provides a feasible pathway for developing positive mixing enthalpy composite materials.
• This approach effectively prevents liquid segregation and controls microstructure for enhanced properties.
• The fabricated composites demonstrate significant improvements in mechanical strength, wear resistance, and hardness.