Microstructural Features and Microhardness of the Ti-6Al-4V Alloy Synthesized by Additive Plasma Wire Deposition...

Area of Science:

• Materials Science
• Metallurgy
• Additive Manufacturing

Background:

• Wire arc additive manufacturing (AM) offers an alternative to traditional Ti alloy production.
• AM-produced Ti parts often exhibit coarse grains, anisotropy, and reduced strength.
• Conventional Ti-6Al-4V parts made by AM lack optimal mechanical properties.

Purpose of the Study:

• To enhance the strength of Ti-6Al-4V alloy produced by wire AM.
• To investigate the effect of using an ultrafine-grained (UFG) wire on Ti-6Al-4V properties.
• To refine the microstructure and improve mechanical characteristics of additively manufactured Ti alloys.

Main Methods:

• Synthesized Ti-6Al-4V alloy using wire deposition welding with a conventional wire.
• Synthesized Ti-6Al-4V alloy using wire deposition welding with an initial ultrafine-grained (UFG) wire.
• Investigated macrostructure, microstructure, phase composition, and microhardness of the samples.

Main Results:

• The UFG wire facilitated increased "crystallization centers" for the α-phase, leading to grain refinement.
• Microhardness of the Ti-6Al-4V alloy produced with UFG wire was approximately 20% higher.
• The UFG structure in the wire contributes to improved mechanical properties in the final AM product.

Conclusions:

• Employing UFG wire in wire arc additive manufacturing is a viable method for enhancing Ti-6Al-4V alloy strength.
• The UFG structure acts as nucleation sites, refining the α-phase and improving microhardness.
• This technique shows promise for improving the mechanical characteristics of additively manufactured titanium alloys.