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1. A SEMINAR REPORT ON
ADDITIVE MANUFACTURING & 3D PRINTING PROCESS
Submitted in partial fulfilment of the requirements for the award of the degree of
BACHELOR OF TECHNOLOGY
IN
MECHANICAL ENGINEERING
BY
CH. ASHISH RAM 20P31A0317
Under the guidance of
Dr. CH.V.V.M.J. SATISH M.Tech, Ph.D
ASSOCIATE PROFESSOR
DEPARTMENT OF MECHANICAL ENGINEERING
ADITYA COLLEGE OF ENGINEERING & TECHNOLOGY
(Permanently Affiliated to JNTUK, Kakinada, Approved by AICTE, New Delhi, Accredited by
NAAC-UGC)
Recognized by UGC Under Section (2f) and 12(B) of UGC Act 1956
Aditya Nagar, ADB Road, Surampalem-533437
2020-2024

2. ADITYA COLLEGE OF ENGINEERING & TECHNOLOGY
(Permanently Affiliated to JNTUK, Kakinada, Approved by AICTE, New Delhi, Accredited by
NAAC-UGC)
Recognized by UGC Under Section (2f) and 12(B) of UGC Act 1956
Aditya Nagar, ADB Road, Surampalem-533437
Department of Mechanical Engineering
CERTIFICATE
This is to certify that the seminar entitled “ADDITIVE MANUFACTURING & 3D
PRINTING PROCESS" is a being submitted by CH.AshishRam,20P31A0317,in partial fulfilment of
the requirements for the award of Bachelorof Technology degree in Mechanical Engineering,
during the academic year 2020-2024. The results embodied in this seminar report have not been
submitted to any other institute or university for the award of any degree.
PROJECT GUIDE
Dr. CH.V.V.M.J. Satish M.Tech, Ph.D.
Associate Professor
Dept. of Mechanical Engineering
Aditya College of Engineering &Technology
HEAD OF THE DEPARTMENT
Dr. Puli Danaiah, M.Tech, Ph.D.
Professor and Head
Dept. of Mechanical Engineering
Aditya College of Engineering &Technology

3. ADDITIVE MANUFACTURING
Introduction to Additive Manufacturing:
AM is the generic term for the collective advanced manufacturing technologies that
build parts layer by layer. The layers are produced by adding material instead of removing
it as opposed to subtractive manufacturing such as machining. The material addition or
fusion is controlled by G-codes generated directly from 3D CAD models. FDM, One of the
AM technologies, builds parts layer by layer by heating a thermoplastic filament to a semi-
liquid state and extruding it through a small nozzle per 3D CAD models usually in STL
format. The filament is usually of circular cross section with specific diameters for each
FDM system. The most widely used diameters are either 1.75 mm or 3.0 mm. Due to the
nature of FDM process, many advantages arise, such as the design freedom to produce
complex shapes without the need to invest in dies and moulds, the ability to produce internal
features, which is impossible using traditional manufacturing techniques. FDM enables the
reduction of the number of assemblies by producing consolidated complex parts. More
advantage of FDM can be reaped through the supply chain by reducing the lead time and
the need for storage and transportation, especially in applications where high customization
is necessary. On the other hand, FDM technology has challenges; such as producing parts
with anisotropic mechanical properties, staircase effect at curves, coarse surface finish, the
need for supports for overhanging regions and more. To overcome these challenges, many
researchers focus on refining the quality of FDM parts. Techniques to improve the quality
of AM or FDM parts, in particular, vary between chemical treatment, machining, heat
treatment, and optimization of processing parameters.
FIG:1 PRINCIPLE OF ADDITIVE MANUFACTURING

4. Over the past years, additive manufacturing (AM) processes have evolved from just being
employed in rapid prototyping techniques to assist in manufacturing methods. The latter
aims to produce finished parts that are economically feasible, robust, with high strength,
and with long-term stability. Moreover, these processes do not require special or costly
tooling for manufacturing the parts, which allows the AM machine to handle a variety of
polymers.
Material extrusion is an additive manufacturing process preferred for building components
due to its low cost, ease of creating complex shapes, and reduced waste. This process is
also known as fused filament fabrication (FFF) or fused deposition modelling (FDM),
which is a trademark name. The FDM method starts by selectively dispensing material
through a nozzle. The polymer is then melted and forced out of the outlet by applying
pressure. The polymer, when extruded, is in a semisolid state, and it solidifies and bonds
with the already extruded material. The nozzle is capable of moving in the XY plane, while
the build platform moves along the z axis. In this way, FDM technology allows for complex
shapes and internal structures.
For many polymers, building material and support material are used during the FDM
process. Both of them are heated and extruded using different nozzles. The support material
holds the structure while printing the layers of the piece. Since this material does not adhere
to the build polymer, it can be removed by submerging the part in a bath.
Despite being a technology that provides several benefits, material extrusion is a
manufacturing process that requires some attention regarding its energy consumption.
Because such electricity is obtained from fossil fuel sources, it generates an environmental
impact. As a consequence, it is vital to optimizing the energy consumption of the FDM
process, along with the typical operation measures (productivity, quality, and structural
performance of the part).
Additive Vs Subtractive Manufacturing:
Additive manufacturing is a process that builds parts from the base up by adding successive
layers to manufacture a product. 3D printing is the technology most associated with
additive manufacturing. Subtractive manufacturing removes material to manufacture a part.
This process traditionally uses Computer Numerical Control (CNC) machining.

5. Both technologies can utilize computer-aided design (CAD) software models to produce
products. These manufacturing technologies have tremendously impacted prototypes and
production and continue to make advancements.
Additive Manufacturing vs. Subtractive Manufacturing: What are Their
Differences?
The differences between additive manufacturing and subtractive manufacturing are
significant. Additive manufacturing, often referred to as 3D printing, adds successive layers
of material to create an object. Subtractive manufacturing removes material to create an
object.
FIG:2 ADDITIVE MANUFACTURING
FIG: 3 SUBTRACTIVE MANUFACTURING

6. Additive Manufacturing:
Both technologies utilize CAD drawings to create parts; additive manufacturing melts or
fuses powder or cures liquid polymer materials to form parts based on the CAD drawings.
Additive processes are slower to manufacture, and several technologies require post-
manufacturing methods to cure, clean, or finish the product. The surface finish is not as
smooth as subtractive manufacturing, and the tolerances aren’t as precise. These processes
are ideal for lighter parts, material efficiencies, rapid prototyping, and small to medium-
batch manufacturing.
Complex geometries, including the printing of articulating joints with additive
manufacturing, are available. The geometries are more complicated, and set-up is quick and
easy, with no operator required during the printing process. The most common materials
used in additive manufacturing are plastics and metals. The equipment cost is less than
subtractive manufacturing, and various material colours are available for most 3D printing
operations.
Subtractive Manufacturing:
Subtractive manufacturing involves material removal with turning, milling, drilling,
grinding, cutting, and boring. The material is typically metals or plastics, and the end
product has a smooth finish with tight dimensional tolerances. A wide variety of materials
are available. Change-overs are longer, but automatic tool changers help reduce time-
consuming delays. The processes can be fully automated, although an attendant may
oversee two or more machines.
The equipment costs are higher and usually require additional jigs, fixtures, and tooling. It
is best suited for large production with reasonably fast manufacturing time but lengthy
changeovers. Material handling equipment helps both processes with material loading and
removal. Geometries are not as complex as additive manufacturing processes.

7. FIG: 4 ADDITVE VS SUBTRACTIVE MANUFACTURING
FUSED DEPOSITION MODELLING:
Fused deposition modelling (FDM) is one of the methods used in 3D printing. This
technique is one of the manufacturing methods under the additive manufacturing
engineering class, gaining popularity among researchers and industry to study and
develop. Additive manufacturing techniques can create various complex shapes and
structures while properly managing materials, resulting in less waste and various other
advantages over conventional manufacturing, making it increasingly popular.
Technically, the FDM technique has the same role as injection molding in the
manufacturing aspect. For example, mass customization. It means producing a series of
personalized items, so that each product can be different while maintaining low prices
due to mass production. It does not need the additional costs of making molds and tools
for customized products.
The basic concept of the FDM manufacturing process is simply melting the raw material
and forming it to build new shapes. The material is a filament placed in a roll, pulled by
a drive wheel, and then put into a temperature-controlled nozzle head and heated to
semiliquid. The nozzle precisely extrudes and guides materials in an ultrathin layer after
layer to produce layer-by-layer structural elements. This follows the contours of the layer
specified by the program, usually CAD, which has been inserted into the FDM work
system.
Since the shapes in FDM are built from layers of the thin filament, the filament thermo-
plasticity plays a vital role in this process, which determines the filament’s ability to
create bonding between layers during the printing process and then solidify at room

8. temperature after printing. The thickness of the layers, the width, and the filament
orientation are the few processing parameters that affect the mechanical properties of the
printed part. The complex requirements of FDM have made the material development
for the filament a quite challenging task.
Research on this material stigmatizes the limitations of the material for this technique.
Currently, 51% of the products produced by the additive manufacturing system are
polymer– plastic filament types. It is because these materials not only have sufficient
criteria to be used and developed but also help to make FDM processes for manufacturing
products more manageable and more optimal. The most well-known polymers used in
this technique are polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS).
Moreover, other materials such as polypropylene (PP) also began to be noticed for
development because it is one of the plastics that is commonly found in everyday life. In
Japan, filaments made of PP are being used and offer superior resistance to heat, fatigue,
chemicals, and better mechanical properties such as stiffness, hinges, and high tensile
strength with a smooth surface finish. Also, several other types of filaments are currently
being developed and introduced as commercial filaments.
Some previous studies showed that although the filament composition is the same, the test
may obtain different results. In other studies, some researchers optimized the performance
of FDM machine by changing some of the parameters and concluded that each combination
of parameters would be showing different results. These studies have shown that many
factors critically determine the results of the FDM process.
This study aims to provide a comprehensive picture of the various factors that influence the
mechanical characteristics of FDM products. The review is carried out by critical mapping
parameters and critical parameters determining FDM factors and analysing each
parameter’s main effects and their interactions in the FDM process. The review starts with
producing the filaments, the impact of different filament materials, and the critical printing
parameters of the FDM techniques. Understanding these factors will be useful to get a
combination of each influential factor, which can later be optimized to obtain printing
results with mechanical properties that can be adjusted to the target application.

9. Filament types
According to its composition, polymer filament is divided into two categories, namely, pure
polymer filament and composite filament. The pure polymer filament is entirely made from
a polymer compound without adding additive solutions. Each type of pure polymer filament
has its inherent characteristics and mechanical properties. Still, sometimes the intrinsic
properties of pure polymers cannot accommodate the need for mechanical properties for
certain products. This problem requires researchers and industries to continuously develop
polymer filaments suitable for commercial needs. One of the steps that can be taken to
improve the mechanical properties of a filament is adding additives to the filament
composition. This process finally led to the composite filament. The following is using
some pure polymer filaments that are often used in 3D printing and development processes.
PLA (Poly Lactic Acid)
PLA is one of the most innovative materials developed in various fields of application. This
type of polymer is thermoplastic and biodegradable. PLA can be developed in medical
applications because of its biocompatibility which is not metabolically harmful. This
process can be achieved by turning it into a filament and then processing it through the
FDM method. The filament can then be converted into various forms commonly used as
implants. The 3D printing scaffolding technique of FDM made a recent development of a
PLA/graphene oxide (GO) nanocomposite material with a customized structure. This study
was carried out to analyze many scaffolding parameters such as morphology, chemistry,
structural and mechanical properties, and biocompatibility to show their potential uses in
biological applications. The study concluded that the use of PLA/GO nanocomposite in 3D
printing is a platform with promising mechanical properties and cytocompatibility, which
has the potential in bone formation application.
The development of PLA-based filaments to improve their mechanical properties has been
carried out comprehensively, starting from testing pure PLA, thermoplastic elastomeric
thermoplastic (TPU) blends, and E-glass fibre reinforced composites (GF). From these
studies, it is concluded that GF as fibre reinforced is generally very beneficial because it
can increase the tensile modulus and flexural modulus. On the other hand, the addition of
TPU provides increased toughness to PLA blends.

10. ABS (Acrylonitrile Butadiene Styrene)
ABS is a general term used to describe various acrylonitrile blends and copolymers,
butadiene containing polymers, and styrene. ABS was introduced in the 1950s as a stricter
alternative to styrene–acrylonitrile (SAN) copolymers.ABS was a mixture of SAN or better
known as nitrile rubber at that time. Nitrile is rubbery, and SAN is glassy and the room
temperature makes this structure an amorphous, glassy, tough, and impact-resistant
material. ABS has complex morphology with various compositions and effects of additives,
therefore making it quite bad in some aspects. However, ABS is a prevalent material used
in the 3D printing process of the FDM method. Still, the choice of other ingredients also
has their respective weaknesses. Researchers carried out various developments to correct
the deficiencies in the mechanical properties of ABS, one of which was to develop an ABS
composite filament reinforced with GO with the addition of 2 weight% GO, made from a
solvent mixing method. This method succeeded in printing the filament ABS into a 3D
model. The tensile strength and Young’s modulus of ABS can be increased by adding GO.
PP (Poly Propylene)
PP is a homopolymer member of polyolefins and one of the most widely used low-density
and low-cost thermoplastic semi crystals. PP applications are generally used in different
industries such as the military, household appliances, cars, and construction because of their
physical and chemical properties. However, PP has low thermal, electrical, and mechanical
properties compared to other engineering plastics (PC, PA, etc.) and has a high coefficient
of friction in dry shear conditions. The mechanical properties of PP are improved by
combining with inorganic fillers in the form of nanoparticles.Friction and wear rate of PP
nanocomposites increase with the applied load and sheer speed. The coefficient of friction
is reduced to 74.7% below the shear speed. Another research tried to compare the printing
ability of PP filled with 30% glass fiber to unfilled PP in terms of mechanical properties.
The addition of glass fibers increases Young’s modulus and ultimate tensile strength of
about 40% for the same printing conditions. Similar enhancements in modules were also
observed for 3D-printed PPs filled with cellulose nanofibrils as well as studies of
optimizing PP compounds that contain spherical microspheres for FDM application by

11. maximizing matrix–filler compatibility that affects printability, properties’ pull, and
toughness. In a concluding impact test on printed composites, the optimized system
exhibited impact energies 80% higher than pure PP.
Printing process on the FDM machine
The FDM machine’s working principle is to heat the filament on the nozzle to reach a
semiliquid state and then extruding it on a plate or layer that was previously printed.
Thermo-plasticity of polymer filaments allows the filaments to fuse during printing and
then solidify at room temperature after printing. Although a simple 3D printing using the
FDM method has complex processes with various parameters that affect product quality
and material properties, each of these parameters is linked to one another, making this
combination of parameters often challenging to understand. In contrast, every product that
results from the 3D printing process has different quality requirements and material
properties. The print parameter combination on the FDM machine is determined by the type
of filament and the size of the filament used in the FDM process.
Therefore, it is crucial to examine the effect of a combination of mechanical performance
parameters. The parameters that affect the printing process are divided into two categories,
namely, the parameters of the FDM machine and the working parameters. Machine
parameters include bed temperature, nozzle temperature, and nozzle diameter. In contrast,
the working parameters include raster angle, raster width, build orientations, etc., and these
parameters are usually inputted in the slicing process using the software before the design
and work parameters are entered into the FDM machine.
APPLICATIONS OF 3D PRINTING:
The use of 3D printing has exploded since the turn of the 21st century and has changed the
traditional ways of manufacturing products. With 3D printers, machines that build complex,
intricate parts layer-by-layer, limited only by the designer's imagination and the capabilities
of the printed materials, seemingly anything can be manufactured. 3D printing, compared
to traditional manufacturing methods such as CNC machining or injection molding,
requires less skill and expertise and less upfront preparation to make parts. From advanced
aerospace components and medical implants to tools and equipment to home decor, the
applications of 3D printing are evidently endless. This article will review 10 applications

12. of 3D printing, and briefly discuss different types of 3D printing, the benefits of 3D
printing, and related topics.
1. Prosthetics
3D printing has revolutionized how prosthetics are created. As 3D printing processes and
techniques are refined, the creation of custom, tailored prosthetics becomes more
straightforward and more efficient. Prosthetics can quickly be modelled in CAD (computer
aided design) software and fabricated by 3D printing. If any errors or defects are found in
a 3Dprinted prosthetic, it can easily be modified in CAD, and reprinted. Consequently, 3D
printing of prosthetics can lead to better patient outcomes, comfort, and satisfaction.
2. Replacement Parts
Another application of 3D printing is the ability to fabricate replacement parts easily. This
can be enormously beneficial to consumers since it reduces both the need to travel to pick
up parts and the long lead times to obtain them. 3D printing enables consumers and
businesses to maximize the value of their purchases and spend more time on more
important matters.
3. Implants
The 3D printing of implants allows the construction of more specialized products for
patients. Patient outcomes are improved when parts with complex geometries can be
fabricated quickly. Items like tooth implants, heart valves, knee replacements, and
maxillofacial implants are all examples of implants that can be 3D printed. Soon, entire
organs could be 3D printed which could dramatically improve outcomes for patients
awaiting transplants. Figure 1 below shows a 3D-printed dental implant:

13. FIG: 5 USE OF 3D PRINTING IN MEDICAL IMPLANTS
4. Pharmaceuticals
3D printing can create drugs of different shapes and sizes and can be used to spatially
distribute active and inactive ingredients in the body. This enables 3D-printed drugs to have
special delivery profiles that can be tailored to patients’ specific needs. While only one
drug, Spritam, a levetiracetam produced by Aprecia Pharmaceuticals has been 3D printed,
3D printing may enable on-demand, local fabrication of additional drugs in the future.
5. Emergency Structures
Natural disasters such as hurricanes, wildfires, and tornados can leave many people
homeless for an extended time. 3D printing can help alleviate the hardships of affected
families by building houses, hospitals, and other structures much faster than the time it
takes to build these structures by traditional means.
6. Aeronautics and Space Travel
As humanity looks to expand its presence in space, 3D printing can be used for the on-
demand fabrication of tools, equipment, and entire structures in space and extraterrestrial
environments. Meanwhile on Earth, 3D printing can be used to produce advanced

14. aerospace components such as airframes, avionics housings, and more. Overall, 3D printing
can help make space travel more cost-effective and consequently aid in creating a
sustainable human presence.
7. Custom Clothing
The fashion industry is notorious for the amount of waste generated by discarded apparel.
3D printing can help alleviate some of this waste by enabling the fabrication of custom
clothing. By allowing consumers the ability to print clothing specific to their measurements
and fashion tastes on demand, consumers can obtain more of what they want with less
waste.
8. Custom-Fitted Personal Products
Many of the objects that people encounter every day are designed with the average body
type or size in mind. Items like doors, chairs, clothing, keyboards, and desks are designed
to be used by a person with an average build within a particular region. This is difficult for
many people who fall outside of these “average build” bounds and can lead to discomfort
and disability. 3D printing allows the creation of custom-fitted personal products which
improve ergonomics, comfort, and safety for everyone.
9. Educational Materials
3D printing can be used to provide students with tangible objects that can be used for
learning. Items like topographical maps or biological replicas can be 3D printed to enhance
learning. As a result, 3D printing can be used to catalyse creativity, better learning, and
foster collaboration.
10. Food
3D printing can also be used to print food. Today, stem cells are already used to make lab
grown meat and vegetables. In the future, 3D printing could be used to produce large
amounts of fruits, vegetables, and meat, which can help to feed the world while reducing
the amount of land dedicated to livestock and farming.