Tailoring Microstructure and Performance of Cu/SiC Composites via Integrated Powder Metallurgy and Thermo-Compression...

Area of Science:

• Materials Science
• Metallurgical Engineering

Background:

• Copper-silicon carbide (Cu-SiC) composites are crucial for structural and thermal management applications.
• Traditional powder metallurgy (PM) processing of Cu-SiC composites often suffers from high porosity and non-uniform reinforcement distribution.

Purpose of the Study:

• To investigate the fabrication of Cu-SiC metal matrix composites using a combined powder metallurgy and thermo-compression processing (PM + TCP) route.
• To characterize the microstructural evolution and mechanical properties of the developed composites.
• To evaluate the effectiveness of TCP as a post-sintering strategy for overcoming limitations in Cu-SiC composite processing.

Main Methods:

• Cu-SiC composites were fabricated by incorporating micro-sized SiC particles (1-25 wt.%) into copper powder.
• The powder mixture was compacted, sintered, and then subjected to sequential forging and annealing (thermo-compression processing).
• Microstructural characterization was performed using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD), and Raman spectroscopy.

Main Results:

• The PM + TCP route significantly reduced porosity and promoted a more uniform dispersion of SiC particles compared to PM-only processing.
• SEM, EDS, XRD, and Raman analyses confirmed phase stability and the absence of deleterious interfacial phases.
• The integrated PM + TCP route achieved optimal properties at approximately 3 wt.% SiC, with an ultimate tensile strength of ~209 MPa, hardness of ~65 HRB, and toughness of ~35 MJ/m³.

Conclusions:

• Thermo-compression processing (TCP) acts as an effective post-sintering strategy, enhancing densification and microstructural refinement in Cu-SiC composites.
• The superior performance of Cu-SiC composites processed via PM + TCP is attributed to uniform particle dispersion, improved particle-matrix bonding, and deformation-driven refinement.
• The combined PM + TCP pathway is a promising method for developing high-strength, thermally stable Cu-SiC materials for demanding applications.