Introduction to Additive Manufacturing Process
What is Additive Manufacturing?
It is a manufacturing process in which 3D CAD
model is used for building component by
depositing materials in layers
Additive Manufacturing commonly referred as
3D Printing
Addition Subtraction
Minimum wastage
Source: https://manufactur3dmag.com
Drilling
Source: https://www.3dnatives.com/
Additive Vs Subtractive Machining
• Material
• Speed
• Easy of use
• Accuracy
• Size limitation
• Geometric complexity
• Cost
History of AM
• In 60s Herbert Voelcker thought of the possibilities of
using computer aided machine control to run machines
that build parts from CAD geometry
• During 70s, he developed the mathematics to describe
3D aspects that resulted in the first algorithm for solid
modeling
• In 80s, Carl Deckard came up with the idea of layer
based manufacturing
• Charles Hull took the credit for development of an
additive manufacturing system (Stereolithography)
during 1986.
Additive Manufacturing
Hopkinson and Dickens’ classification
• Stereolithography
Liquid Based • Jetting Systems
Raw material:
• Direct Light Processing
Highly viscous liquid
• Selective Laser Sintering
• Three-Dimensional Printing
• Fused Metal Deposite Systems
AM Processes • Electron Beam Melting
Powder Based • Selective Laser Melting
Raw material:
• Selective Masking Sintering
In powder form • Selective Inhibition Sintering
• Electro photographic Layered
Manufacturing
• High Speed Sintering
• Fused Deposition Modelling
Solid Based
• Sheet Stacking Technologies
Raw material:
Filament form / Thin wire
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ADDITIVE MANUFACTURING
Rapid Prototyping in a nutshell
1. 3D CAD model of the desired object is generated
2. The CAD file is typically translated into STL*
format
3. The object described by the STL file is sliced
along one direction (the ‘z’ or ‘printing’ direction)
4. Each slice is manufactured and layers are fused
together (a variety of techniques exist). The
material can be deposited by dots (0D), lines
(1D) or sheets (2D)
*The STL (stereo lithography) file format is supported by most CAD packages and is
widely used in most rapid prototyping / additive manufacturing technologies.
STL files describe only the surface geometry of a three-dimensional object without any
representation of color, texture or other common CAD model attributes. The STL file
describes a discretized triangulated surface by the unit normal and vertices
coordinates for each triangle (ordered by the right-hand rule).
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*Source: ENG 165-265Spring 2017, Dr. Marc Madou
re thickness, Less thickness,
surface finish Finer finish &
smooth outlines
Advantages of AM
• Complex geometry with no additional costs
• Build speed; reduction of lead time
• No expensive tooling required
• Dimensional accuracy
• Wide range of materials (polymer, ceramic,
metal,..)
• Green manufacturing
Limitations of AM
• Part size small
• Most suitable for mass
customization rather than mass
production
• Materials: Non weldable
materials are difficult to
process by AM
• Properties: Could achieve
99.9% density with some
residual porosities
• Inferior to cast/wrought metals
Case Studies of AM
Aerospace Industry
• The engine for Orbex Prime has been 3D printed by SLM Solutions on an SLM 800 large
format additive manufacturing system
• it is made in a single piece, eradicating joins and strengthening the part’s overall integrity
• It is made from nickel alloy, and its additive production has saved Orbex 90% in turnaround
time and over 50% in costs compared to traditional CNC machining.
• The engine reportedly helps make the Prime “30% lighter and 20% more efficient than any
other launch vehicle in its category
Source: https://3dprintingindustry.com/news/slm-solutions-3d-prints-landmark-single-piece-
rocket-engine-for-orbex-148726/
Biomedical applications
Pharmaceutical Industry
• 3D Printing of personalized
medicine
• Producing controlled
release tablets
Additive Manufacturing
The assembly can be personalised
and printed in one process.
Food 3D printer
Concrete Printer
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