Manufacturing Processes is the title of the subject. The document outlines the teaching scheme, examination scheme, syllabus and internal assessment for the subject. The syllabus covers 6 units - casting processes, melting and molding, joining processes, conventional forming processes, advanced forming processes, and advanced manufacturing processes like rapid prototyping. Rapid prototyping involves 5 main steps - CAD modeling, CAD conversion, STL model slicing, model fabrication using techniques like stereolithography, selective laser sintering, fused deposition modeling and post-processing. It has advantages like reduced design time but also limitations such as material properties.

2. Teaching Scheme & Examination
Scheme
Theory/Lectures – 3 Hrs. /Week
Practical– 2Hrs. /Week
ESE: 70 Marks
ISE: 30 Marks
ICA – 25 Marks
OE: 25 Marks

3. Syllabus:
Unit-1: Basics of Casting Processes
Definition of casting, Basic steps in casting processes, Advantages,
limitations and applications of casting process, General introduction to
patterns, Types of patterns, materials used, Allowances, types of cores
and core boxes, molding materials and its properties, Gating system,
types of risers, Function of riser, method to improve efficiency of
risers. Riser design simple numerical problems.
Unit-2:Melting, Molding and Inspection processes
Construction and working in brief of melting furnaces such as Cupola,
Arc furnaces, induction furnaces. Green sand molding (hand and
machine molding), Shell molding, Investment casting, centrifugal
casting, gravity and pressure die casting processes. Stages in fettling,
Common important defects in castings. Inspection procedure,
Computer applications in foundry processes, foundry Mechanization.

4. Unit-3:Introduction to Joining processes Welding processes,
classification of welding process, arc welding, welding rod
selection, TIG welding & MIG welding, submerged arc welding,
gas welding, resistance welding, Brazing and soldering.
• Unit-4:Conventional Forming Processes
Introduction to forming process, Classification of forming
processes, forging, types of forging, simple numerical problem
on upset forging. Extrusion, Types – direct extrusion, indirect
extrusion, impact extrusion, hydrostatic extrusion, Wire drawing
process, Methods of tube drawing, hot rolling, cold rolling of
sheets, classification of Rolling mills, theory of rolling, simple
numerical problems on rolling.

5. Unit-5:Advanced Forming Processes
Introduction to advanced forming process, High energy rate
forming process- explosive, Electro-hydraulic, magnetic pulse
forming. Forming with hydrostatic pressure- hydro mechanical and
hydro forming process.
Unit-6:Advanced Manufacturing Processes
Introduction to Rapid prototyping (RP), Basic principles,
Classification, Steps in RP,
Advantages, disadvantages and applications of RP, Stereo
lithography - Selective Laser Sintering (SLS), Selective Powder
Binding (SBP), Fused Deposition Modeling (FDM), Direct Metal
Laser Sintering (DMLS), Advantages, disadvantages and
applications.

6. Internal Continuous Assessment (ICA):
1. Design of pattern and core for a simple component.
2. Testing of silica sand for grain fineness and clay content.
3. Testing of green sand for green compression strength,
permeability.
4. Study of mold for moisture content and core hardness tester.
5. Study of manufacturing sequence of upset forging with
example.
6. Study of VI characteristic of welding process.
7. Visit to Foundry unit.
8. Visit to forging shop.

7. Text Books
• 1. Heine, Lopar, Rosenthal, Principles of Metal
Casting.
• 2. N.D. Titov, Foundry Practice.
• 3. P.L. Jain, Principles of Foundry Technology.
• 4. P.N.Rao, Manufacturing Technology:
Foundry, Forming and Welding.
• 5. Production Technology by P.C. Sharma

8. • Manufacturing Processes (Title of the
Subject)
• Manufacturing – To produce or to make
• Processes – Method or way of doing

9. Unit No. 6
Advanced
Manufacturing
Processes
Manufacturing Processes

10. Rapid prototyping (RP) is a technology and apparatus for
fabricating physical objects directly from parts created in
CAD using additive layer manufacturing techniques without
manufacturing process planning, tooling, or fixtures.
Rapid prototyping is an essential part of the user interface
design process. It allows designers and product managers to
test new concepts and theories with users and create a final
solution that has been validated before handoff.
Following are the types of rapid prototyping technology
available for engineering product designers: Additive
manufacturing – Stereolithography (SLA), Selective laser
sintering (SLS), Direct metal laser sintering(DMLS), Fused
Deposition Modelling (FDM), Binder jetting and Poly jetting.

13. Step #1. CAD Modeling
The rapid prototyping steps typically begin with a solid model in CAD.
The valid model represents the design of each part. Designers can use
pre-existing files to customize a component or create single-use
examples. Many existing CAD files only require minor modifications to
support a complex RP order.
Step #2. CAD Conversion
CAD programs utilize various algorithms, so designers must work
diligently to ensure quality, accuracy, and consistency. Generally, they
use an STL format as the rapid prototyping standard. Operators need to
convert the CAD file into STL for cohesion and to define the three-
dimensional boundaries.
(STL is a file format commonly used for 3D printing and computer-
aided design (CAD). The name STL is an acronym that stands for
stereolithography — a popular 3D printing technology. Standard Triangle
Language or Standard Tessellation Language)

14. Step #3. STL Model Slicing
Experts will bring your finished STL model to the slicing program for
further processing. This is one of the essential rapid prototyping steps
because it allows teams to make last-minute adjustments to the
design. They can change the size, swap the orientation, or switch
locations of various aspects before manufacturing.
Step #4. Model Fabrication
The rapid prototyping steps continue when the tool patterns for
building and supporting the structure are created. Operators fabricate
a prototype using one of the multiple build techniques established.
Meanwhile, most RP machines are fully automated and produce parts
one layer at a time using the STL model.
Step #5. Post-Processing
Post-processing is the final rapid prototyping step. It involves taking
the prototype off the machine and detaching any support structures
produced during fabrication. Depending on the materials and desired
appearance or strength, some designs might require photocuring,
cleaning, surface treatments, or finishing

15. Advantages:
Reduced design & development time
Reduced overall product development cost
Elimination or reduction of risk
Allows functionality testing at a fraction of the cost
Disadvantages:
Rapid prototyping required skilled labour
Limited material range
Reduced material properties like surface finish and strength
Some rapid prototyping processes are still expensive and not
economical.
Applications:
Rapid prototyping is widely used for surgery planning, diagnosis,
training, and custom implant design and manufacture. 3D
computer-aided design and manufacturing are also used to design
and develop new medical products. They shorten the time to

16. Selective Laser Sintering:

17. Principal:
Selective laser sintering is an additive manufacturing (AM) technology that uses a
high-power laser to sinter small particles of polymer powder into a solid structure
based on a 3D model.
Working:
1. Sintering in SLS primarily occurs in the liquid state when the powder
particles forms a micro-melt layer at the surface, resulting in a reduction in
viscosity and the formation of a concave radial bridge between particles,
known as necking, due to the material's response to lower its surface energy.
2. In the case of coated powders, the purpose of the laser is to melt the surface
coating which will act as a binder.
3. Solid state sintering is also a contributing factor, albeit with a much reduced
influence, and occurs at temperatures below the melting temperature of the
material.
4. SLS 3D printing has been a popular choice for engineers and manufacturers
for decade.
The term SLS is typically only used to refer to plastic and ceramic 3D printers
— metal 3D printers using a similar process are referred to as DMLS or SLM
machines.

19. Selective Powder Binding:
Step by Step
A layer, typically 0.1mm thick of material is spread over the build
platform.
A laser fuses the first layer or first cross section of the model.
A new layer of powder is spread across the previous layer using a roller.
Further layers or cross sections are fused and added.
The process repeats until the entire model is created. Loose, unfused
powder is remains in position but is removed during post processing.

20. Powder Bed Fusion is a 3D printing technology spawns products
with precision.
This 3D printing technique enables the manufacturing of a vast
array of geometrically complex products using a heat source,
mainly laser or electron beams, to fuse powder particles layer-by-
layer, therefore forming a solid part.

21. Fused deposition Modeling:
Principle:
Fused deposition Modeling (FDM) is a manufacturing technology that
uses a moving nozzle to extrude fibers of polymeric material layer-
by-layer in order to build a structural design. FDM is mainly used for
mechanical system modeling, fabrication, and production.

22. Construction & Working:
The FDM process starts with importing an STL file of a model into a pre-
processing software. This model is oriented and mathematically sliced
into horizontal layers varying from +/- 0.127 - 0.254 mm thickness.
A support structure is created where needed, based on the part's
position and geometry. After reviewing the path data and generating the
toolpaths, the data is downloaded to the FDM machine.
The system operates in X, Y and Z axes, drawing the model one layer at a
time. This process is similar to how a hot glue gun extrudes melted beads
of glue.
The temperature-controlled extrusion head is fed with thermoplastic
modelling material that is heated to a semi-liquid state.
The head extrudes and directs the material with precision in ultrathin
layers onto a fixtureless base.
The result of the solidified material laminating to the preceding layer is a
plastic 3D model built up one strand at a time.
Once the part is completed the support columns are removed and the
surface is finished.

24. Direct metal laser Sintering (DMLS):
Direct metal laser sintering (DMLS) is an AM technique for metal 3D
printing. In this process, the metal powder (20 μm diameter), free of
binder or fluxing agent, is completely melted by the scanning of a high-
power laser beam. The resulting part has properties like the original
material.

25. While Binder Jetting uses a binding agent to bond metal particles
together and EBM uses an electron beam to melt the metal
powder, Direct Metal Laser Sintering (DMLS) uses a laser to melt
the metal powder resulting in instant solidification.
High-resolution DMLS builds at a layer thickness of 0.0008
in. (0.02mm) and can produce quite accurate parts, with
tolerances to +/- 0.003 in. (0.076mm), part features as small as
0.006 in. (0.152mm), and surface finishes similar to that of a
sand casting.
DMLS is a 3D printing process, which uses a computer-
controlled, high-power laser beam to melt and fuse layers of
metallic powder together. Direct metal laser sintering (DMLS) is
an industrial 3D printing process that builds fully functional -
rapid metal prototypes and production parts in 7 days or less.