Undergraduate Category: Engineering and Technology Degree Level ...
Undergraduate Category: Engineering and Technology Degree Level: MechE, sophomore Abstract ID#769
Integra(ng S(ff Electronic Components with Flexible Polymer Substrates
Robin Hanqiu Li and Randall M. Erb
Sintering ceramics
Abstract
In order to increase the durability of cell phones, companies are seeking to introduce flexible characterisLcs to cell phone casings. As it’s an essenLal part of a cellphone casing, the antenna also needs to be flexible to withstand certain level of bending. 4 methods to construct a flexible antenna were proposed by Directed Assembly of ParLcles and Suspensions (DAPS) Lab which were 1) producing a mixture of ceramics and polymers, 2) infiltraLng polymers in the antenna structure, 3) refilling sintered ceramics with polymer, and 4) building a layered structure for an antenna.
• • • • • •
Backfilled method
Second stage of the research Take samples from Stage 1 Sintered following sintering protocol 3-‐point bend test Flexural strength for sintered ceramics is 3.25MPa Flexural strength for unsintered ceramics-‐polymer is 45.7MPa
• • • • • •
Integrated design
SLll a work in progress Based on previous research Take all the samples from previous stages Form a layered design in order of gradual change in sLffness • 3-‐point bend test • Expected to have rather high flexural strength • Might be the soluLon • • • •
Background
With the development of technology, commercial mobile phones have undergone several tremendous changes such as decreasing in size while increasing mobile processing capabiliLes. At this point, the next challenge will be adding flexibility to the casing in order to increase the durability of the phone. However this feature cannot be accomplished without making the most fundamental component— the antenna—flexible.
Third Stage of the research SLll a work in progress Take sintered samples from Stage 2 Refilled with polymer 3-‐point bend test Expected to have rather high flexural strength
Pre-‐sintered samples Sintering oven
Ceramics-‐polymer Mixture • • • • •
First stage 20wt%PVA & iron fillings Degas mixture then dry evaporate water content at 60 degree Celsius Average tensile strength Average Modulus is 1.527 Gpa
Stretchable heterogeneous composite research[1]
Flexural Test Flexural Test finish Flexural Stress Vs. Extension 3.5
3
2.5
Stress (MPa)
Degas chamber 2
1.5
1
0.5
Stretchable heterogeneous composite research[2]
0 0
0.05
0.1
0.15
0.2
0.25
Extension (mm)
Summary & Future Work
Flexural Stress VS. Strain
• Ceramics-‐polymer mixture has potenLal to be the most flexible design among all • ConLnue to determine permi^vity and other electrical properLes of the design • ConLnue to determine flexural strengths and modulus of the last two methods
Stress VS. Extension 60
Tensile TesLng Samples
50
Stress VS. Strain
40
30 Stress (MPa)
Stress (MPa)
25 20
30
20
15 10
10 5
0 0
0 0.000% 0.500% 1.000% 1.500% 2.000% 2.500% 3.000% 3.500% 4.000% 4.500% Strain
Sample 3 Sample 4 Sample 1 Sample 2 Tensile Stress VS. Strain graph
-‐10
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Extension (mm) Unsintered Sintered
Compared Flexural Stress VS. Strain
Future concept [1] [2] Libanori, Rafael, Randall M. Erb, Alain Reiser, Hortense Le Ferrand, MarLn J. Süess, Ralph Spolenak, and André R. Studart. "Stretchable Heterogeneous Composites with Extreme Mechanical Gradients." Nature CommunicaLons 3 (2012): 1265. Web.
Integra(ng S(ff Electronic Components with Flexible Polymer Substrates
Robin Hanqiu Li and Randall M. Erb
Sintering ceramics
Abstract
In order to increase the durability of cell phones, companies are seeking to introduce flexible characterisLcs to cell phone casings. As it’s an essenLal part of a cellphone casing, the antenna also needs to be flexible to withstand certain level of bending. 4 methods to construct a flexible antenna were proposed by Directed Assembly of ParLcles and Suspensions (DAPS) Lab which were 1) producing a mixture of ceramics and polymers, 2) infiltraLng polymers in the antenna structure, 3) refilling sintered ceramics with polymer, and 4) building a layered structure for an antenna.
• • • • • •
Backfilled method
Second stage of the research Take samples from Stage 1 Sintered following sintering protocol 3-‐point bend test Flexural strength for sintered ceramics is 3.25MPa Flexural strength for unsintered ceramics-‐polymer is 45.7MPa
• • • • • •
Integrated design
SLll a work in progress Based on previous research Take all the samples from previous stages Form a layered design in order of gradual change in sLffness • 3-‐point bend test • Expected to have rather high flexural strength • Might be the soluLon • • • •
Background
With the development of technology, commercial mobile phones have undergone several tremendous changes such as decreasing in size while increasing mobile processing capabiliLes. At this point, the next challenge will be adding flexibility to the casing in order to increase the durability of the phone. However this feature cannot be accomplished without making the most fundamental component— the antenna—flexible.
Third Stage of the research SLll a work in progress Take sintered samples from Stage 2 Refilled with polymer 3-‐point bend test Expected to have rather high flexural strength
Pre-‐sintered samples Sintering oven
Ceramics-‐polymer Mixture • • • • •
First stage 20wt%PVA & iron fillings Degas mixture then dry evaporate water content at 60 degree Celsius Average tensile strength Average Modulus is 1.527 Gpa
Stretchable heterogeneous composite research[1]
Flexural Test Flexural Test finish Flexural Stress Vs. Extension 3.5
3
2.5
Stress (MPa)
Degas chamber 2
1.5
1
0.5
Stretchable heterogeneous composite research[2]
0 0
0.05
0.1
0.15
0.2
0.25
Extension (mm)
Summary & Future Work
Flexural Stress VS. Strain
• Ceramics-‐polymer mixture has potenLal to be the most flexible design among all • ConLnue to determine permi^vity and other electrical properLes of the design • ConLnue to determine flexural strengths and modulus of the last two methods
Stress VS. Extension 60
Tensile TesLng Samples
50
Stress VS. Strain
40
30 Stress (MPa)
Stress (MPa)
25 20
30
20
15 10
10 5
0 0
0 0.000% 0.500% 1.000% 1.500% 2.000% 2.500% 3.000% 3.500% 4.000% 4.500% Strain
Sample 3 Sample 4 Sample 1 Sample 2 Tensile Stress VS. Strain graph
-‐10
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Extension (mm) Unsintered Sintered
Compared Flexural Stress VS. Strain
Future concept [1] [2] Libanori, Rafael, Randall M. Erb, Alain Reiser, Hortense Le Ferrand, MarLn J. Süess, Ralph Spolenak, and André R. Studart. "Stretchable Heterogeneous Composites with Extreme Mechanical Gradients." Nature CommunicaLons 3 (2012): 1265. Web.
