POWDER METALLURGY-BASED PRODUCTION OF HIGH-ENTROPY ALLOYS: STRUCTURAL AND FUNCTIONAL EFFECTS OF SI ADDITION

Hadi BİLİR¹ , Mehmet Akkaş² , Can Doğan VURDU³

In this study, a CrMnFeCoNi-based high-entropy alloy (Cantor alloy) was modified by the addition of 5 wt.% silicon (Si) to develop a composite structure with improved microstructural and mechanical properties. Si was selected based on its potential to promote phase stability and reinforcement, as well as its frequent use in similar studies. Elemental powders were homogenized via high-energy ball milling to ensure uniform mixing and enhanced atomic-scale dispersion. The mechanically alloyed powders were compacted through uniaxial cold pressing at 600 MPa to increase green density and interparticle contact. Sintering was conducted at 1000?°C in a controlled atmosphere to activate solid-state diffusion and facilitate phase formation and densification. Microstructural characterization was performed using scanning electron microscopy (SEM). The analyses revealed that Si addition influenced the distribution of the reinforcement phase, porosity, and particle morphology. Notably, phase evolution, pore formation, and particle dispersion were strongly affected by both the presence of Si and the applied sintering conditions. The results indicate that 5 wt.% Si significantly enhances microstructural integrity and contributes positively to the overall mechanical performance of the composite material.

Keywords
High-Entropy Alloys (HEAs), Powder Metallurgy, Silicon Addition, Microstructure, Mechanical Properties,