Rapid thermokinetics driven nanoscale vanadium clustering within martensite laths in laser powder bed fused additively manufactured Ti6Al4V

• Main Authors: Mangesh V. Pantawane, Sriswaroop Dasari, Srinivas Aditya Mantri, Rajarshi Banerjee, Narendra B. Dahotre
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2020-10-01
• Series: Materials Research Letters
• Subjects: additive manufacturing; selective laser melting; vanadium enrichment; thermal modeling
• Online Access: http://dx.doi.org/10.1080/21663831.2020.1772396
• ISSN: 2166-3831

This paper reports the computational approach adopted for thermo-diffusion kinetics to rationalize homogenously distributed nanoscale vanadium-rich clusters formed within the martensite laths of Ti6Al4V alloy printed using laser powder bed fusion at an energy density of $52.08\,{\rm J}/{\rm mm}^{3} $. The computations were conducted using a finite element method based thermal model, which predicted extremely rapid thermokinetics associated with the thermal cycles experienced at any given location of LPBF-printed Ti6Al4V. The numerically estimated effective V diffusion length of 6.61 nm indicated kinetic-limited diffusion resulting in V nano-clusters and are in good agreement with the atom probe tomography data giving a value of half the inter-cluster spacing of 7 nm.