NUST Institutions Library Catalogue

From the past few years, Additive Manufacturing (AM) or 3D printing has
achieved a significant role among the latest emerging technologies of the
fourth industrial revolution. 3D printing strategy allows us to build
components of various materials without any geometrical constraint. This
feature is unique in the field of industrial production, and it has transformed
the traditional manufacturing concept of mechanical design permitting
lightweight components and improving stiffness. Moreover, another
advantage of additive manufacturing is decreased production waste and
energy consumption. The Nickel based Super Alloy powder has its wide
applicability in the defense industry and mainly Aero-Engine components.
This can also be used for biomedical, power generation and automotive
applications. Nickel and its alloys are useful due to their properties at elevated
temperatures. The aim of this research was to develop the build parameters of
Nickel based powder and successfully print functional parts using Selective
Laser Melting (SLM) process. The properties desired for the functional part
have been verified through mechanical testing. The print worthiness of this
powder along with desired results achieved through this research has led to
qualified printing of metal parts for high temperature applications. In the
presented thesis, the objective was to conduct a series of experiments to
develop parameters for printing Nickel based superalloy K465 powder for
aero-engine applications. The properties that were evaluated against the
printing parameters include Actual Density measurement, Microstructure and
Tensile values. The best samples were optically viewed to look for
microstructure. Alongside metallography, UTS samples were printed to carry
xv
out mechanical testing of the best samples. The experiment yielding finest
results was chosen for functional part printing. Though additive
manufacturing of nickel-based superalloys presents significant technological
advancement, their unique material behavior and properties also present
several common challenges like fusion of layers, microstructure control,
residual stress and cracking during 3D printing that require careful
consideration and process optimization. The K465 superalloy powder is also
prone to cracking which was faced during this research. Though higher preheat temperatures were provided to mitigate this issue, cracking couldn’t be
avoided due to available SLM limitation. To avoid this challenge, the further
optimization of developed K465 parameters can be carried out through EBM
process and even through more R&D and advanced strategies at SLM
machine discussed in this thesis. These studies will be crucial for optimizing
K465 additive manufacturing processes and ensuring the production of crackfree, high-integrity components for the most demanding applications.