Additive manufacturing of a crack-free CM247LC Ni-superalloy by alloying

Project description

The highly adaptable laser powder bed fusion (LPBF) methods used in additive manufacturing (AM) enable more design freedom and near-net-shape fabrication, which increases process efficiency and decreases material waste. Nevertheless, there are significant obstacles in the way of fabricating high-performance materials, such as Ni-based superalloys, using additive manufacturing techniques, particularly LPBF. In particular, the AM of nickel-based superalloys is frequently linked to prominent texture, microstructural inhomogeneities, and stress-induced micro/macro cracking. This is especially true for superalloys with high γ′ and γ′′ contents. One such class of Ni-superalloys with a high propensity for processing-induced cracks is CM247LC.The deposition of high γ′ superalloys is linked to several cracking mechanisms, including as solidification, strain-age, and liquation cracking, with strain-age and liquation cracking being the more challenging to regulate.
Even when precise process parameter and microstructure control is used to create parts free of cracks, post-deposition procedures such hot isostatic pressing and precipitation heat treatments may result in recurrent cracking, rendering the component unfit for use. These problems explain why AM-LPBF CM247LC alloy’s creep strength is much lower than that of its cast equivalent.

The initial phase of this research will modify the alloy to increase the printability of CM247LC, enabling the additive manufacturing of specimens free of cracks. The high temperature properties of AM of modified-CM247LC will be tested against an AM-friendly innovative superalloy composition of ABD900-AM in the second half of this study as a benchmarking for creep resistance. To compare, a test matrix would be created.

Outcomes

1. Investigate the feasibility of using innovative microstructural or process design to produce a Ni-superalloy CM247LC that is free of cracks, as it is otherwise very vulnerable to processing-induced cracking.Next, contrast its high temperature characteristics with those of a new AM superalloy. 2. A patent 3. Three to six publications in worldwide peer-reviewed journals.

Essential capabilities

BTech in Materials or Mechanical Engieering; MSc in Physics (solid state) with CSIR-JRF or DST-Inspire fellowship (own funding)

Desireable capabilities

Knowledge on basic sold state physics and metallurgy including materials thermodynamics and mechancial behaviour of materials

Expected qualifications (Course/Degrees etc.)

BTech (Mech or Mater Engg) or MSc (Physics ) with own CSIR-JRF or DST-Inspire funding

Additional information for applicants

Note: i-students must have own scholarship to apply (CSIR, UCG-NET, etc)