Mechanical Alloying of Ball-Milled Cu–Ti–B Elemental Powder with the In Situ Formation of Titanium Diboride

Abstract

This paper represents the fabrication and characterization (microstructural, mechanical, and electrical) of Cu-2wt% B-4 wt% Ti and Cu-5wt% B-10wt% Ti alloy from the ball-milled Cu, Ti, and B powders. The in situ formation of TiB2 was also discussed in the light of differential scanning calorimetry (DSC) and X-ray diffraction (XRD). This present work investigates the effect of various parameters on powder production and the formation of in situ TiB2 through the thermo-mechanical route. The apparent activation energy during metastable phase formation for the two types of alloy composites has been calculated using the Johnson-Mehl-Avramani (JMA) equation and found to be 567.46 and 626.37 (KJ/mol), respectively. However, the findings of this study indicate the mechanical properties of the composite are due to the in situ formation of TiB2 particles in the Cu matrix. The properties of the composites after heat treatment were discussed employing mechanical and electrical properties and measured ultimate tensile strength (UTS) (~375 MPa), yield strength (~300 MPa), and hardness (~150 Hv) for a higher percentage of Ti and B addition. The electrical conductivity also decreased to 53% IACS as Ti negatively impacts conductivity.

Keywords

• ball milling
• Cu
• TiB₂
• XRD
• SEM
• TEM