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April 29, 2004 Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter
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April 29, 2004 Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Feb 22, 2016

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April 29, 2004 Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter. Overview. Goal Etchants Volume Fraction Infiltration!! Backfilling a Preform Increasing Volume of Tin-Lead Future Plans Gantt Chart. Tin-Lead Etchants. Ethanol Nital 1% solution - PowerPoint PPT Presentation
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Page 1: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

April 29, 2004

Edward BarnardElizabeth Hager

Kevin McComberJenny Lichter

Page 2: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Overview• Goal• Etchants• Volume Fraction• Infiltration!!• Backfilling a Preform• Increasing Volume of Tin-Lead• Future Plans• Gantt Chart

Page 3: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Tin-Lead Etchants• Ethanol

• Nital– 1% solution– Approximately 45 seconds– Revealed grain structure of metals

Page 4: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Volume fraction• Why we care:

– High pressure in our process can potentially allow for the the infiltration of higher volume fraction of ceramic particles

– Yields hard, lightweight materials with good fracture toughness properties

• Determined by– Theoretical calculations– Optical imaging and image processing

Page 5: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Calculating Volumes and Average Density

r = (1/6)*h+(1/2)

r

h

Volume = 2*(19π/32) h = 1.5 in

Volume = (4/3)(π)(0.53)= 0.52Volume = 4.25

Calculating volume fraction:- weigh part- MMC weight = part weight – (tin lead)*(Vtin lead )- (ceramic)*(Vceramic ) + (tin lead)*(1-Vceramic ) = MMC

Vceramic = 70 % for sintered SiC, 120 grit

Page 6: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Preparation and Imaging• Tried to cut with hacksaw, band saw

– Was too hard!!

• Cut with diamond-coated wheel• Polished to 4000 grit

– Scratches still remained– Scratches confuse volume fraction calculations based

on images from optical microscope– Thus very good polishing necessary

• Imaged with optical microscope

Page 7: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Image Processing• Used MATLAB• Set threshold brightness to section image into

matrix and ceramic• Integrate and average over many images to get

average area fraction

• For isotropic materials:Area Fraction = Volume Fraction

Page 8: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Infiltrated Al2O3 Preform

Alumina <Vp>= 39 %

Page 9: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Infiltrated SiC preform• 58.9 + 7.1 % Ceramic

Page 10: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Backfilling a Preform• Backfilling important for complicated shapes

• Our plan: insert plate to demonstrate backfilling

Backfilling: red arrows

Backfilling: red arrows

Page 11: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Increasing metal

Alter runner setup toaccommodate metal

Sn-Pb

Mold Mold

Page 12: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Future plans• Further optical imaging

– Fracture behavior– Volume fraction

• As already mentioned– Backfilling– Increasing metal

• Final Prototype

Page 13: April 29, 2004  Edward Barnard Elizabeth Hager Kevin McComber Jenny Lichter

Gantt Chart2/5 2/12 2/19 2/26 3/4 3/11 3/18 3/25 4/1 4/8 4/15 4/22 4/29 5/6 5/13

MaterialsMetal choiceCeramics choice

Part productionCADAlum. machined mold

Ceramic preform

Volume fraction Time PermittingSize distribution "

Final testing

CODE:Task Sub-task Gradation Testing