This document is a final report submitted by a group of mechanical engineering students to their professor for a project designing and building a powder rolling mill fitted with spark plasma sintering. The report details the design of the machine, which aims to simultaneously roll and sinter powdered aluminum into a continuous strip. It includes sections on the problem definition, concept generation and evaluation, final design embodiment, and a liability statement. The group is proud to present not only the design report but a working prototype to the professor.

1. Final Paper
[DAN-10]
Pulse Electrical Current Assisted Sinter
Rolling Mill
Mechanical Engineering Project
[MECH-463]
Presented to:
Dr. Amar Sabih
Prof. Mathieu Brochu
Group 28
ANANIAN, Harout 260 235 752
SAUCIER ROBERTSON, Derrick 260 236 646
SHIRRY, Wassim 260 232 985
WARD, Jacob 260 231 853
McGill University
Department of Mechanical Engineering
April 14th
, 2010

2. Dear Prof. Mathieu Brochu,
Our team is proud to present to you not only our final design report but also a working
aluminum powder rolling mill. All members of our group have put in an enormous effort to ensure
that the final prototype is not only of upmost quality but also meets the requirements you specified in
September. As you know we have extensive documentation of the design, production and testing
phases, not only in the DAN reports but also in our personal design notebooks. We have enclosed the
previous DAN reports with any other relevant materials on a CD-ROM for you to review and keep
for your records.
Our team would like to take this opportunity to thank you for the proper financial and
technical support you provided. Without it our machine would not have been a success. As
graduating mechanical engineering students we found this project to be an excellent introduction to
designing and manufacturing at a professional level and greatly enjoyed working with the Materials
Engineering Department.
This project has been a source of great joy and pride and we hope that you are happy with the
results.
Enjoy your new machine!
Sincerely,
----------------------------- ----------------------------- ----------------------------- ----------------------------
H. ANANIAN D. ROBERTSON W. SHIRRY J. WARD
Group 28
Mech. Eng. Project - 2010

3. Liability Statement
This project is part of a Mechanical Engineering Project Course of the Faculty of Engineering of
McGill University. It is meant to fulfill academic objectives by having students apply their knowledge
to the development, design, and construction of a prototype which responds to the needs identified by
the sponsor. The project is first and foremost a training tool for future engineers, which brings
invaluable experience to us.
The fact that the prototype in development by the students be fit for commercial, industrial, or private
use is not a primary objective of the project. We strive to provide the client with a machine that
works, but it will not necessarily be fit to withstand the rigors of regular use, and as such we do not
guarantee the device’s adequate and consistent performance over time.
The prototype in development will only be a prototype, and must be fully checked for safety before
being put to use. For instance, it may be necessary to design emergency shut-off switches and other
safety features. Some of these features will be mentioned in the design documentation, but there may
be others that were not thought of. The safety of those using the machine should always be a primary
concern and users should be properly trained to avoid accidents.
McGill University, its students, employees, professors, agents and governors decline any
responsibility with respect to the prototype, its performance and

4. GR28 – DAN 10 1
Abstract - The machine referred to in this report aims to
produce continuous material from powdered metal.
Rolling of powdered materials is used to create a
continuous sheet material. After rolling, the formed metal
must be sintered conventionally. Our project aims at
combining the spark plasma sintering (SPS) technology
with a powder rolling mill. Such a process is desirable as it
will yield a continuous strip or sheet of material with the
desired properties provided by the spark plasma
technique. As of yet, minimal amount of work has been
done on continuous SPS manufacturing. In fact, there are
no commercial machines today capable of producing SPS
sintered strips.
The finished product produced the desired green strip
upon first try and proved that it could be done.
Index Terms: Powder Metal, Rolling Mill, SPS, Sinter.
I. INTRODUCTION
he expanding field of material engineering and metallurgy
has been on the rise for quite some time, touching upon
different aspects of everyday life. New discoveries and
novel ideas are dramatically changing the world by improving
material properties, finding new ways of production and
manufacturing, and even crafting new materials out of old
ones. One can even reduce all around costs without sacrificing
quality; in fact, increasing quality is more than commonplace.
Spark Plasma Sintering (SPS), also called Field Assisted
Sintering Technique (FAST) or Pulsed Electric Current
Report Submitted on April 14, 2010. This work was supported by Dr. Mathieu
Brochu.
All Authors of this report are currently undertaking an Undergraduate
degree in Mechanical Engineering at McGill university, and can be contacted
at the following emails:
Harout Ananian, Harout.Ananian@mail.mcgill.ca
Derrick Robertson, Robertson.Derrick@gmail.com
Wassim Shirry, Wassim.Shirry@mail.mcgill.ca
Jacob Ward, Jacob.Ward@mail.mcgill.ca
Sintering (PECS) is a somewhat new process in the domain of
powder metallurgy. It is been around since the late 30’s, but
the technology and research has only started to emerge in the
last 10 to 15 years.
SPS is an alternative powder sintering technique that allows
the production of fully dense materials within minutes, while
applying high heating rates and short dwell times. The process
consists in compressing the powdered metal and applying a
large pulsed DC current with typical pulse durations of 10 ms
[1] (see Figure 1). This greatly reduces heating and cooling
times, since it is being heated inside-out versus the
conventional sintering method which heats the sample outside-
in.
Figure 1: Basic SPS set-up [2].
Current powder sintering is costly, time consuming, and
promotes grain growth within the metal. The SPS powder
rolling mill will be designed to eliminate all of these
inconveniences related to conventional powder sintering. As
an example, a small powder “green” must be sintered in a
furnace for many hours to achieve required properties. An SPS
machine can give better results with a more desirable grain
structure in around five minutes [3].
Rolling of powdered materials is used to create a continuous
sheet material. After rolling, the formed metal must be
Pulse Electrical Current Assisted Sinter
Rolling Mill
Group No. 28
Harout Ananian, Derrick Robertson, Wassim Shirry, Jacob Ward
Client: Dr. Mathieu Brochu, McGill Materials and Mining Department, Montreal, Qc
Advisor: Dr. Amar Sabih, McGill Mechanical Engineering Department, Montreal, Qc
T

5. GR28 – DAN 10 2
sintered conventionally. Our project aims at combining the
spark plasma sintering technology with a powder rolling mill.
Such a process is desirable as it will yield a continuous strip or
sheet of material with the desired properties provided by the
spark plasma technique.
II. PROBLEM DEFINITION
The problem defined to us by the customer is to design and
build a powder rolling mill fitted to utilize spark plasma
sintering in order to simultaneously roll and sinter the powder.
The ultimate goal of the project is to roll and sinter a strip of
aluminum, initially in powder form, approximately 2 mm
thick, 25 mm wide, and 300 mm long. Additionally, the intent
is to conserve the nanostructure of the initial material in order
to enhance its physical properties. The addition of powder
rolling techniques to SPS technology is not only possible, it is
essential for the notion of producing a continuous
nanostructured aluminum strip.
The electrically sintered strip will then be examined by the
client to insure that the product has the desired properties.
These include such attributes as proper grain size, grain
density, and material properties such as hardness and tensile
strength.
However, due to certain financial issues, the client changed
the objective of the project. Instead of sintering
simultaneously while rolling with SPS, now we are sintering
once the green strip exits the rollers. This will be done via an
induction coil placed under the rollers (see Figure 2).
Figure 2: Induction heating schematic [4].
The way induction heating works is simple. A source of
high frequency electricity is used to drive a large alternating
current through an induction coil. The passage of current
through this induction coil generates a very intense and rapidly
changing magnetic field in the space within the work coil. The
work piece to be heated is placed within this intense
alternating magnetic field [4]. Due to issues with the heater
supplier and McGill, this part has yet to have been received.
III. CONCEPT GENERATION
The conceptual design phase is arguably the most important
part of the design process. In this phase, ideas and concepts
are first generated and later evaluated based on their merit.
Consideration is given to such aspects as: precision and ease
of controls, availability of materials and components,
difficulty of manufacturing, and the overall quality of the end
product. As we strived for the perfect design, we put great
effort into making some difficult decisions and compromises
without sacrificing performance. Each concept was assessed
on the same basis, with the same criteria, such that an
objective comparison of competing designs was performed.
The machine performing the task constitutes various
components and sub-systems. The main parts of the general
design are:
 a hopper to contain the powder and control
distribution,
 a compacter in the form of a rolling mill,
 a sintering apparatus, and
 a driving mechanism.
IV. CONCEPT EVALUATION
A. House of Quality
Quality function deployment (QFD) is a method to
transform user demands into design quality, to deploy the
functions forming quality, and to deploy methods for
achieving the design quality into subsystems and component
parts, and ultimately to specific elements of the manufacturing
process [5].
The House of Quality matrix, within the realm of QFD
tools, was used to graphically represent the client’s
requirements versus the technical design requirements. It
translates customer needs into an appropriate number of
engineering targets to be met by a new product design. This
tool allowed for a good overview of the relations between the
WHAT’s and the HOW’s surrounding the project.
The QFD can be seen on the next page. From this
evaluation, we were able to determine that the most important
consideration for the machine, as follows:
1. Number of components
2. Dimensions / Length
3. Cost of components
4. Thickness of green strip
5. Angular Velocity
6. Elastic Modulus of Material
7. Surface speed

6. GR28 – DAN 10 3
Figure 3: House of Quality of alternate designs
Column #
Direction of Improvement:
Minimize (↓), Maximize (↑), or Target (X)
Row#
MaxRelationshipinRowValue
RelativeWeight
Weight/Importance
Quality
Chracteristics
"Hows"
Customer Requirements
"Whats"
1 9 7.8 3.5 Ease of Manufacturing
2 9 4.4 2.0 Cost of Materials / Components
3 9 8.9 4.0 Speed Control of Rollers
4 9 11.1 5.0 Gap Control of Rollers
5 9 11.1 5.0 Easy to Interchange Components
6 9 8.9 4.0 Stuctural Integrity of Machine
7 3 10.0 4.5 Drive Train Adjustability
8 9 6.7 3.0 Ease of Operation
9 9 4.4 2.0 Size
10 9 11.1 5.0 Rollers
11 9 6.7 3.0 Frame
12 9 4.4 2.0 Vacuum Chamber
13 9 4.4 2.0 Hopper
Target or Limit Value
Max Relationship in Column Value
Weight / Importance
Relative Weight
9 3
1
9 1 9
1
91 3 1 3 3 1
3 3 3 1 3 1
9 3 3 3 3 1 3 1 1
1
9
3 9 3 3 1 3 9 3 3
3 9 3 9 3 3 1 9 9
7.2 10.1 11.5 9.4
1 9 3 3 1
257 358 409 332
9 12.8 10.3 10.3 2.7 2.6
9 9 9 9
Target
3 3 9
321 453 367 364 95.6 91.1
9 9 9 9 3 3
13 1 3 1
LimitValue
LimitValue
LimitValue
LimitValue
Target
Target
X X X
Target
Target
Target
3
SurfaceSpeed(mm/s)
Thicknessofgreenstrip(mm)
Dimensions/Length(m)
1 1 3
+
X
ElasticModulusofMaterial(MPA)
NumberofComponents(#)
TotalWeight(Kg)
CostofComponents($)
CyclestoFailure(#)
OperatingTemperatureRange(°C)
↑ ↓ ↓ ↓ X X
AngularVelocity(rpm)
132 3 4
∆
3 3 9 3
5 6
+ ∆ +
∆ ∆ + +
1
7
∆
8 9
9 9 1
9 3 3 1
1
3
CoefficientofThermalExpansion(1/°C)
1
9
3
9 9
140 161
3.9 4.5
9 9
Target
LimitValue
∆
3
AngleofRollers(degrees)
X
12
3
1
1
9 9
10 11
X ↓
ElectricalConductivity(Ω-1)
∆ +
+ + +
+∆ ∆
∆ + ∆
+ +
+
9 3 3 3 3
9 1 3 9 9
+ +
+
∆
3 3 3 1 9
Legend
Strong Positive Correlation: ∆
Positive Correlation: +
201
5.7
+
∆
∆
+
3
9
3
3
Target
9

7. GR28 – DAN 10 4
B. Apparatus Specifications
In reality, the project is to design a compacter and sintering
mechanism. Various factors have to be taken into
consideration and constantly re-evaluated to ensure proper
quality of the end product. These were accomplished with the
use of certain assumptions, educated guesses, and just plain
logic.
The following lists the specifications that were deemed
most crucial for what is required based on the client’s needs:
 The size of the rollers has to guarantee proper
compression in order to get a high green density.
 The rollers will perform the task of the compactor.
 All components in contact with the rollers must
resist high temperatures.
 The rollers must rotate at the exact same rate.
 The system must be able to compress the powder
with a total force of about 50 MPa.
 A hopper may be placed over the rollers; it will
contain all the powder and distribute it evenly to
the compacter.
The final machine has all components physically able to be
assembled without any unreasonable complications. It is
important to note that one of the main factors in deciding
which concept was superior was the ease of future
modifications, if needed.
V.DESIGN EMBODIMENT
After detailed examination of each concept and with the
help of the selection matrices we determined a final concept
that will fulfill our client’s needs. Figure 4 is a table of the
various components that will comprise our prototype.
There are many different components and mechanisms that
must be considered to fully understand the system in question.
Figure 4: Final subassembly layouts.
A. Rollers
The selected concept is the most basic and rudimentary. The
powder is fed from the hopper and compressed by the rollers
into a green strip. The general roller setup is one of the most
important aspects of the machine; it is the source of the
compaction. For this reason a high strength was selected.
This design has the advantage of being very simple.
Furthermore, it has proved to be very effective in conventional
powder rolling. Another pro is that its symmetry allows
powder to be easily fed by gravity.
In order to provide the proper compaction, a roller of
400mm was used. The roller is attached by bolts to a plate that
is welded to the shaft. The reason we attached the roller in this
way is that once the prototype is functioning, the steel roller
could be replaced.
B. Driving mechanism
The driving mechanism is a key aspect for the proper
functioning of the system. The rollers must turn at a very
precise rate; hence the driving mechanism provides a
relatively perfect motion.
The sprocket with the arrow is attached to the motor (it’s
the drive). The two equal sized sprockets are connected to the
shafts of their respective roller. The final sprocket is there to
provide the proper tension on the chain. A good aspect of this
driving mechanism is the fact that it may provide a gear
reduction option.
C. Frame
Due to the required compression of the powder, there will
be larges forces applied to the frame. In addition, the thickness
of the desired strip is very small. Thus, the frame will have to
be high in strength and very rigid in order to properly resist
the forces and not deform the overall shape causing an
increase in the thickness of the strip.
The whole frame is made of three different varieties of
structural steel. The main box that supports the rollers and
pillow blocks was made from C-channel steel, the support
between the rollers have a square cross-section, and the width
and hopper holler are to be constructed of angle iron. The
frame has been designed to be as stiff as possible to reduce the
deflection of the rollers. Moreover, all the steel is made of
standard sizes, so they were easy to purchase. The overall
setup was made such that there was minimal time spent for
manufacturing.
D. Edge Control
This concept is to have one of the rollers have two large
diameter disks attached on both of its sides. Edge control
prevents the powder from escaping from the side of the rollers.
It will ensure proper material formation at the very edge of the
roller. It must have minimal friction between the edge
controller and the powder as to not add unwanted forces.
As the system turns, so does the disk. This ensures that the
edge of the strip has the same properties as the rest of the
material. This system prevents the powder from falling out the
sides, and it also creates a nice edge at the extremities of the
strip.

8. GR28 – DAN 10 5
E. Hopper
The hopper must be able to deliver powder at a uniform
feed rate to the rollers. The feed rate of the powder changes
the final density of the compacted stip. Therefore, an
interesting option is to have a feed adjustment mechanism.
A funnel shaped hopper encloses a paddle wheel. The wheel
is driven by a DC motor. Adjusting the voltage to the motor
will change the rotation speed and thus the feed rate.
Figure 5: Final draft of CAD
VI. FABRICATION
The fabrication process took roughly two months, and we
were able to manufacture each component of the machine in
house. The technicians in the machine shop provided us with
extremely valuable advice and expertise. They helped us from
day one and we incorporated their ideas into the production
process and into our final design.
A. Rollers and Shafts
The rollers and the shafts were the longest and most
complicated pieces to construct. Ordering premade rollers was
out of the question due to their high cost. Therefore they had
to be machined from two 17in square plates of heat treated
4340 steel. The fabrication of these rollers was complicated
due to the strength of the material and their size.
Figure 6: Rough cutting rollers with band saw.
The first step for the roller construction was to “rough” out
the circular shape on a band-saw. This process took 3 hours of
work per roller. Once the shape was cut, it was placed onto a
lathe, between pressure plates so that the outer diameter could
be made circular. Once the outer diameter was turned we held
the piece in a very large four jaw chuck to bore the inner
diameter. Due to the strength of the material, a few cutting
tools were broken during this process.
Attachment plates, to fasten the rollers to the shafts, were
made from scrap metal that was given to us by the client.
These were made in the same way as the rollers. Six holes
were then made in the plates and rollers so that they could be
fastened together. The holes in the big rolls were taped so that
the bolt would screw in.
Figure 7: Roller with attachment plate.
The next step was to make the shaft. It was fully machined
on the lath. The thicker section was turned to the size of the
rollers (2.500”) and the other section was made to fit the
pillow block bearings (1.750”) that would hold the set up to
the frame. The very end of each shaft was turned to 1.500”,
and a keyway was cut in order to fit the driving mechanism.
Figure 8: Early stages of the shafts.
Once all components were completed, the attachment plate
was welded to the roller. The finished shaft with attachment
plate was put back onto the lathe to ensure that the attachment
plate was perfectly perpendicular to the shaft. The roller was
then bolted to the shaft and the assembly was placed onto a
lathe in order to center the outside diameter.

9. GR28 – DAN 10 6
Figure 9: Shafts with attachment plates welded on.
B. Driving Mechanism
Most of the driving mechanism consisted of premade parts.
Power for the machine was provided by a 2 HP single phase
farm duty electric motor. The motor was coupled to two gear
boxes in series with a pulley and best system. Both gearboxes
and motor were old farm equipment and purchased used at
bargain prices.
Figure 10: Motor and gear box set-up.
The sprocket and chains were all ordered from General
Bearing Store (GBS) in Montreal. The inside diameters of the
sprockets were bored to 1.500” and a keyway was cut so that
could be fastened to the shafts of the gearbox and roller
assembly
An idler sprocket had to be manufactured because ordering
one had a very long lead time. We did this by increasing the
size of the inner diameter of a small sprocket and pres-fitting a
custom made brass bushing. This bushing was fabricated from
a special material called Oilite, which is specifically used for
bushings. The inside diameter was made to that of a 3/4’ bolt
that the final sprocket would idle on. The tensioner on which
this part is attached was made from steel that we had left over
from the frame.
The gearboxes and motor attachment were made from steel
and welded to the frame. Great amounts of time and energy
went into the alignment of the drive mechanism. We had to
ensure that the gearboxes were mounted perfectly
perpendicular to one another and also that the output sprocket
was in line with the sprockets on the rollers.
Figure 11: Motor track and gear box brackets on frame.
C. Frame
The frame was fairly simple and the first element to be
fabricated. The first step was to cut the structural steel to
length using a horizontal band saw. The components were
then clamped into place and welded together. Although simple
to build, the final product was very heavy (about 400lbs)
which caused some transportation problems. We resolved this
problem by fitting the frame with four heavy duty casters
(wheels).
Figure 12: Frame ready to be painted.
D. Edge Control
The edge guards became somewhat of a manufacturing
problem due to their shear size. None of the schools lathes
were big enough to turn the outer diameter of these parts. The
simplest solution to this problem was to use a rotary table on a
milling machine. We roughed out the outer diameter on the
band saw before clamping them to the rotary table. The cutting
tool on the milling machine remained stationary and the piece
was rotated slowly to cut the outside diameter. The inner
diameter was cut using a CNC circle program on the same
milling machine. The bolt holes on the plates were also cut at
the same time using a bolt pattern program. The full process
took a full day. These edge guards were then bolted to one of
the rollers.

10. GR28 – DAN 10 7
Figure 13: Milling the edge guards.
E. Hopper
The material used for the hopper came from a galvanized
steel air-duct given to us by Prof. Brochu. Sheets were cut
from the duct using a grinder. In order to transfer the
dimension onto the sheets, templates of the CAD were printed.
The final shape was cut using a band-saw. Bending turn out to
be more complicated than expected because of the number of
bends and the thickness of the material. In fact, one sheet
needed no less than 7 bends. In order to accomplish this task,
the usual bending machines were out of the question, so a
table, a hammer, and a piece of wood was used. The two parts
were then clamped together and welded. The original design
cone tip, however, was reshaped to a slot to accommodate the
client’s preferences. In order to do this, the tip was grinded
and welded back together. Bondo was used to conceal any
holes and imperfections.
Figure 14: Hopper still in two pieces.
F. Paint
The final step before assembly was to paint all the
components. The paint used is a high gloss polyurethane
enamel by SICO called Corostop. It will provide a durable
lasting finish and protect the machine from rusting. The color
blue was decided upon because the pillow blocks were already
that color. Prior to painting, the frame was scrubbed using a
buffing pad on an angle grinder in order to remove all weld
splash. Areas such as pillow block and motor mounts were
protected using masking tape.
G. Final Assembly
The final assembly went smoothly. All part where put into
place and adjusted. We spent a great deal of time setting the
roller gap to exactly 2.0mm using a custom made feeler gauge.
Also the sprockets were aligned so that the chain would
function properly and roll smoothly. The chain was then cut to
length and installed on the machine. The idler was semi
permanently attached to it nut using Locktite.
Figure 15: Final assembly being transported.
VII. PROTOTYPE DESCRIPTION AND PERFORMANCE
While constructing the prototype, adjustability and
versatility was of upmost importance; we wanted minimal
effort to be needed to modify the arrangement.
To adjust the gap for example, the bolts for the pillow
blocks need to be undone and then the roller assembly can be
moved. Again, in order to remove or tighten the chain, two
socket bolts on the idler support need to be loosened.
One of the major concerns was the speed of the rollers. The
AC motor that was bought does not have any speed variation;
the output speed can be modified only by varying the size of
the pulleys relaying the motor and the first gearbox. To
simplify the operation, a mount was constructed so that the
motor can be slid into a position to accommodate different
sizes of pulleys and straps (see Figure 10).
Our initial belief was that the machine would be able to
have a large quantity of powder on the rollers. However, after
the first test, we instantly realized that too much powder

11. GR28 – DAN 10 8
caused the rollers to stall. Therefore, the level of the powder
needs to be tightly controlled in order to not stall the machine.
However, since we have only tested one powder and it was
very talky, to say the least, no proper generalization can be
made at this point. Hence, to produce the green strip, the
powder was spoon fed into the gap. To prevent the “hour-glass
effect”, a piece of paper is initially placed to block the gap.
After a few tries after the machine stalled, an adequate
powder level was found that produced consolidated material.
The result was very impressive, a solid strip of metal that
could be manipulated without shattering.
Figure 16: Consolidated aluminum powder
Figure 17: Compacted powder 'stuck' between edge guards.
The final product has an important fault: it is curved. The
reason for this is that when the material is compressed, it gets
squished between the two edge guards. In fact, the only way to
remove the strip is by removing these parts from the machine
and the strip just falls out.
The curvature of the strip would be tolerable if the surface
finish would not have been affected. Yet the final product is
quite brittle; the added radius causes fracture lines on the
surface that is in tension. The compressed side shows no
visible modification. We believe that the strength of the green
strip would be increased if it was straight because there would
not be existing defects. Furthermore, since the machine is for
microstructure analysis and research, this problem would need
to be fixed. Our recommendation on this problem will be
discussed in the next section.
VIII. CONCLUSION AND RECOMMENDATIONS
To conclude, the powder did consolidate and we were able
to roughly produce a 2 mm thick, 25 mm wide, and 300 mm
long green strip, as stated in the objective. However, as
previously discussed, the product is curved. In order to mend
this problem a few options are possible.
The first is to see if reducing the friction between the edge
guards will solve the problem. Graphite paint could be used to
coat the guards. This could reduce the friction enough to make
a straight strip. In order to prevent breaking, a guide would
need to be placed right after the gap. This piece could simply
be a flat metal bar. Its sole purpose is to prevent the green strip
from snagging on the roller.
The second method would be to change the guard set-up
altogether. It could be replaced with a simple plate or a more
complicated set of rollers. This would solve the problem
because they would not be following the rollers. Having a
plate would increase the friction of between the rollers, but
this is not an important consideration. More importantly, it
could affect the quality of the edge by causing to crumble.
However, it is much simpler to construct than a roller set-up.
Another issue with the machine is concerning safety. The
chain has to have a chain guard to prevent some accidents
even if the rollers are rotating at a very slow speed. The main
danger is from the chain snapping because the powder causes
a stall. Another consideration for the chain would be to add a
tensioner on the loose side. This would increase the safety and
prevent teeth from skipping which could cause something to
break.
Another improvement that can be made is to add a metal
plate above the motor and the gearboxes to cover them from
potential powder spills. In addition, since the motor does not
have an on (forward)/off/on (reverse) switch, we recommend
having one.
The hopper that we constructed is not ideal for this
machine. The feed rate must be tightly controlled. The actual
construction and conceptualization could actually be a project
on its own. It is very important to note that the machine can
suffer catastrophic failure if too much powder causes a stall in
the rollers. The only way to solve the problem is to run the
motor in reverse.
Our final machine can easily be modified to accommodate
other sintering methods such as SPS. The support shafts have
a huge safety factor. The only aspect that needs to be
considered for SPS is the electric isolation.
ACKNOWLEDGMENT
We would like to thank all the people working in the
machine shops that helped us fabricate this machine. Without
them, it would most likely be a pile of scrape metal.
REFERENCES
[1] http://sirius.mtm.kuleuven.ac.be/Research/C2/Modelling%20of%20Fiel
d%20Assisted%20Sintering.htm
[2] Mochizuki. “Manufacturing technique of Nb3Al super-conductive sheet
by electrically heated powder rolling”, 1999.
[3] http://www.spssyntex.net/whats/whats3.html
[4] http://www.gpgyjr.com.cn/
[5] Akao, Yoji. "Development History of Quality Function Deployment".
The Customer Driven Approach to Quality Planning and Deployment.
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