High-Temperature Diffusion Bonding of Ti–6Al–4V and Super-Duplex Stainless Steel Using a Cu Interlayer Embedded with Alumina Nanoparticles

• Main Authors: Kavian O. Cooke, Anthony Richardson, Tahir I. Khan, Muhammad Ali Shar
• Format: Article
• Language: English
• Published: MDPI AG 2020-01-01
• Series: Journal of Manufacturing and Materials Processing
• Subjects: stainless steel; titanium; diffusion bonding; nanoparticles; intermetallic compounds; grain size reduction
• Online Access: https://www.mdpi.com/2504-4494/4/1/3

In this study, Ti−6Al−4V alloy was diffusion bonded to super-duplex stainless steel (SDSS) using an electrodeposited Cu interlayer containing alumina nanoparticles to determine the effects of bonding parameters on the microstructural evolution within the joint region. The results of the study showed that the homogeneity of the joint is affected by the bonding time and bonding temperature. The results also showed that when a Cu/Al₂O₃ interlayer is used, Ti−6Al−4V alloy can be successfully diffusion bonded to SDSS at temperatures above 850 °C. The combination of longer bonding time and high bonding temperature leads to the formation of various intermetallic compounds within the interface. However, the presence of the Al₂O₃ nanoparticles within the interface causes a change in the volume, size, and shape of the intermetallic compounds formed by pinning grain boundaries and restricting grain growth of the interlayer. The variation of the chemical composition and hardness across the bond interface confirmed a better distribution of hard phases within the joint center when a Cu/Al₂O₃ interlayer was used.