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Materials Science in Additive Manufacturing High-performance materials in AM

in office environments to fabricate paper models. The
problem with SHL technology, however, is that it cannot
be used to print complex structures, so the practical value
of this technology is limited.
A similar technique called electron beam sheet
lamination (EBSL) has recently been attempted in the
manufacture of turbine disk alloys with good results .
[50]
EBSL technology utilizes electron beams to achieve rapid
melting and solidification between multiple layers of
material. This feature helps control the segregation of the
alloy itself and removes impurities in the alloy to obtain
Figure 7. Schematic of selective laser melting build chamber and products of higher purity. The alloy prepared by EBSL has
process . a finer structure and exhibits good creep rate.
[36]
new aluminum alloy with low thermal crack sensitivity 2.7. Vat photopolymerization
suitable for PBF printing technology was fabricated and VPP technology is incredibly special compared to other
was shown to achieve the highest strength currently AM technology. During the process, a light source of a
known for aluminum alloys printed by PBF . For specific wavelength is selectively directed at a specific part
[45]
other aluminum alloys such as Al-Zn-Mg-Cu-Nb alloys, of a barrel of photosensitive liquid material to induce a
the effect of Zn content on the formability and aging curing reaction, during or after which the build platform is
precipitation that may result from LPBF preparation has lowered and the surrounding liquid material re-submerges
also been studied . It has been demonstrated that the the platform and a new layer is cured . Depending on
[46]
[51]
content of the Zn element affects the aging kinetics, the the light source used and the way the platform is lowered,
order of elemental precipitation and the crystal size of the VPP technology can be classified as continuous direct
alloy, provided that the PBF printing technique is used. It light processing, direct light processing, stereolithography
was also explored how the processing window changes as (SLA), etc. [52,53] .
the Zn content rises to ensure that it can be stabilized for The principle of this technique therefore limits the
fabrication .
[46]
range of materials that can be applied to VPP. The usual
There are numerous studies exploring in this regard, raw material is photosensitive liquid resin, but fillers such
indicating that the intensive investigations of the PBF as ceramics can be added to enhance the mechanical
technology are a testament to its current dominance. properties of the finished product . In addition, a new
[54]
study has offered a solution to the problem of switching raw
2.6. Sheet lamination
materials during the process, enabling the use of multiple
Sheet lamination (SHL) technology is known to be the first materials in printing embedded complex structures .
[55]
commercialized AM technology, but its market share is Compared to other AM technology, VPP technology
still very limited today [47,48] . The raw material requirement offers the advantages of high precision, fast forming,
for SHL technology is sheet or plate. During the process, smooth surfaces and low material waste . However,
[56]
these raw materials are stacked layer by layer and tooled to this technology has a few disadvantages, such as high
cut out specific sections for gluing or welding, which are costs, limited adaptability of raw materials and potential
combined to form the structure.
instability in the performance of the finished product. The
Over the years, SHL technology has evolved into various field of bioprinting based on VPP technology is currently
sub-categories including selective deposition lamination, gaining traction. By varying the type of photo initiator
ultrasonic additive manufacturing and selective lamination used, VPP technology can produce finished products that
composite object manufacturing, depending on the type of are simultaneously reliable and highly biocompatible. VPP
raw materials used and the bonding process, which vary in technology also has considerable potential for application
detail but are based on the same principle . in the field of tissue engineering and regenerative
[49]
[57]
Due to these adaptable variants, SHL technology can medicine .
process a wide range of materials such as metals, paper, The application of VPP technology improves the
polymers, textiles, ceramics, and composites and can be scalability and also eases the replication and manufacture
used to build very large finished products [47,49] . Some of the of organs-on-a-chip [58,59] . Two sub-types of VPP
3D printers using SHL technology can also be deployed technology – SLA and DLP – have proven to be the most

Volume 2 Issue 3 (2023) 6 https://doi.org/10.36922/msam.1587