ALDO SOBERON ELECTRONIC ENGINEERING PORTFOLIO

TABLE OF CONTENTS

Resume: pg 3 Career Plan: pg 4

Interest/Techical Project Paper: pg 14 Personal Statement: pg 24

Recommendation Letter: pg 25 Capstone Presentation: see attached powerpoint

Aldo Soberón 780 East Tonto Drive | Chandler, AZ 85249 | (480) 751-8717 | asoberon@asu.edu

EDUCATION: B.S.E. Aerospace Engineering, Arizona State University Grad. December 2019 National Hispanic Recognition Program Scholar GPA: 3.49/4.00 National Academy of Engineering Grand Challenge Scholars Program National Science Foundation Academic Success and Professional Development Program Scholar Society of Hispanic Professional Engineers SKILLS: MATLAB, LabVIEW, SolidWorks, Visual Basic, ANSYS, GD&T, Lean Manufacturing (TPS), Autonomous Vehicle Systems, Spanish

EXPERIENCE: Northstar Aerospace, Mechanical Engineering Intern May 2018-Present - Submit customer rework packages ($1500/ea) detailing defects/corrective actions from Material Review Requests, particularly

on Apache and Chinook transmissions (~50 hr/wk) - Create AS9102 and In-Process Inspection sheets to communicate Engineering’s blueprint/MOT changes to

machinists/inspectors and make corrections to technical drawings - Designed First Pass Yield system in VBA for Director of Quality Assurance to document all Inspection jobs to reduce package

errors/correction time and to record error metrics - Helped continuous improvement of processes by increasing parallel machining/reducing inspection time - Assisted Level III operator in non-destructive testing (liquid penetrant, magnetic particle and radiography) - Contributed to successful audit for AS9100D certification by correcting documents to meet export control protocol

Adaptive Intelligent Materials & Systems Center, Research Assistant 2017-2018 - Studied carbon nanotube effect on carbon fiber composite damage performance through high-velocity impact tests, looked

for delamination/spalling/fiber fracture etc., first author on study - Examined stress/strain during tensile test using ARAMIS Digital Image Correlation for mechanical characterization - Invited to present technical paper at 2018 AIAA SciTech Conference, funded by ASU Fulton Undergraduate Research Initiative

and Army Research Office, presented to NASA and Army Research Laboratory

Army Educational Outreach Program, URAP Research Intern Summer 2017 - Optimized capabilities of single stage light-gas gun to >1000 m/s and >4000 J using self-designed laser diode velocimeter - Self-taught LabVIEW to create program to record laser voltage, used MATLAB to find velocity from voltage data on NI-DAQ

LEADERSHIP: Grand Challenge Scholar Alliance (National Academy of Engineering), President 2015-Present - Design and present workshops to introduce new skills, primarily to freshmen (MATLAB, SolidWorks, machining, 3d printing) - Create opportunities for members to graduate as GCSP scholars via research, service learning, alumni panels etc. - Coordinate outreach events; i.e. industry panels, Phoenix Children’s Hospital Days, Girls Make-A-Thon, STEM Saturdays etc.

Formula SAE, Aerodynamics Team Member 2017-2018 - Analyzed pressure/velocity maps over car body in ANSYS/SolidWorks to determine poor air flow areas - Designed/improved structures in SolidWorks to optimize aerodynamics of competition car

Promise Arizona (PAZ), Volunteer Team Lead Summer 2016 - Led team of five high school volunteers at night class where immigrants developed English/tech skills and job outlook - Provided instruction through English conversations and reading exercises at South Mountain Community College

PROJECTS: Autonomous Aircraft Capstone, Team Member Aug. 2018-Present - Working with Northrop Grumman/The Aerospace Corp. engineers to finalize requirements from Request for Proposal (RFP) - Conducting preliminary design review for Mission Adaptive Modular Platform UAV under Dr. Frederick Garrett

Light-Gas Gun Optimization, Project Lead Summer 2017 - Improved laser velocimeter design to use inexpensive laser ($6) after original laser failed ($102) - Increased max velocity by ~500 m/s via propellant switch from N to He, 3D printed projectiles, streamline simulations

COMPREHENSIVE CAREER PLAN

SUMMARY OF GOALS AND OBJECTIVES

As an aerospace engineering major, I originally thought that I would ultimately work solely in the

aerospace industry working as an aerodynamicist or structural engineer. Eventually, I believed, the

private space industry would mature and I would be able to join a firm working on spacecraft or

satellites. However, I have recently gained much interest in the automobile industry after speaking

with industry engineers from firms such as Ford. As of now, I would like to work as a systems

engineer or work in flow or structural analysis of vehicles.

CURRENT STATUS

Currently, I am working on a Bachelor’s Degree in Aerospace Engineering, with a concentration

in Aeronautics. With the curriculum offered here at ASU I believe I have built a robust foundation

in structural mechanics, control systems, thermodynamics and aerodynamics. As such, I feel that

once I have graduated I will be a good candidate for mechanical and aerospace entry-level junior

engineering positions.

I am looking forward to courses developing my skills in structural analysis, aerodynamics, and

more recently, control systems. I would also like to take elective courses in CFD and would also

like to take CAD II to develop ANSYS usage skillsets. I have been wary of taking two advanced

control systems classes next semester (space vehicle dynamics and control as well as aircraft

dynamics and control) but they really seem as if they will provide a competitive advantage where

modern engineers must be able to assume many roles and not be pigeon-holed into one specific,

rigid role. Additionally, it will allow me to better work and understand other engineers in an inter-

disciplinary team. I have learned recently that I am really interested in programming and electrical

systems and I am considering finding roles with a heavy emphasis in control systems. I believe

these course swill help greatly in achieving that.

In terms of professional preparation, I have done much but there are several areas in which I would

like to improve. I have iterated on my resume through several versions but I still have not received

a review from the career center which would help in the presentation of my skills and help me be

better received by hiring managers and engineers. My cover letter has also gone through several

iterations but I tend not to tailor it for each application. I have heard from recruiters that, many

times, documents are not read, especially cover letters, are oftentimes not read and therefore I am

not sure I should change my habits on cover letters. My preparation for internships has allowed

me to receive many interviews. In fact, I have already received an offer from Boeing, am traveling

to Seattle for final-round interviews I will continue to apply in order to maximize my chances.

My social life is quite healthy. In the past, I have had problems with social interaction, especially

with figures of authority. However, throughout my college career I have been working on this and

I believe I am now doing much better than when I came to Arizona State. Unfortunately, this

semester I think I have gone overboard in that there was a time where I was going out several

functions every weekend and the consequences in the days after were that I was lethargic and

therefore less productive. I used it as a form of escapism and so my scholarly, research and career

interests have suffered noticeably. Although my social life has begun to thrive and I feel more

comfortable around people, like during interviews, I realize now that I must be more responsible

with recreational activities.

Economically, I think I am in a better position than many. My scholarships, including the ASAP

scholarship are paying for the entirety of my schooling and rent and my parents have thankfully

elected to pay for my food. Unfortunately, I do have some loans from the first two years of my

college career. However, the stipends that I have received from the Fulton Undergraduate Research

Initiative (FURI) and the Army Research internship I worked at a previous summer Undergraduate

Research Apprenticeship Program (URAP) are going to be used to pay for these. I use my current

internship wages from Northstar Aerospace to pay for food and gas to school. As such, I expect to

leave ASU with very little to zero in terms of debt. I am very proud of this accomplishment as I

am essentially putting myself through college while studying, working and conducting research at

a prestigious center.

EDUCATION

I will always believe that education is the greatest tool for socioeconomic mobility, and not

necessarily education from a formal institution. My degree in engineering I believe will propel me

to rise above the circumstances I was raised in. My parents came from Peru with very little. Their

degrees were not recognized and thus they work jobs they are overqualified for and have sacrificed

much more for me. Some day, I wish to return the favor for all they have taught me and provided

for me to thrive.

I wish to continue my learning but I am not sure which degrees and in what disciplines would be

most beneficial for me. Currently, I am deciding between whether to pursue a MS/PhD or MS in

engineering or an MBA. I really would like to lead teams of engineers and eventually move on to

overseeing more business-related activities as a manager. I am unsure what degrees or experiences

paths would provide the best chances for the realization of this goal. I plan to speak with my

mentors and hope to establish contacts in industry in order to apply some of their learning and

experiences.

During my summers, I think I have shown that I am not willing to rest on my laurels and during

them I have continued to develop my skills and abilities. My first summer, I took differential

equations at a community college an I worked as a volunteer English teaching assistant helping

recent adult immigrants learn how to read, write and speak as well as helping them write resumes,

use search engineers and take advantage of the resources afforded to them. Last Summer, I worked

on a project at the Adaptive Intelligent Materials & Systems (AIMS) Center at ASU funded by the

Army Educational Outreach Program (AEOP) under the Undergraduate Research Apprenticeship

Program (URAP). This summer, I would really like to work at The Boeing Company or Ford

Motor Company and am waiting on their response after my interviews. However, any engineering

internship will be helpful in the end.

RESEARCH EXPERIENCE

High-Velocity Impact Assessment and Mechanical Characterization of Carbon Nanotube

Embedded Composite

Aldo Soberón, Nithya Subramanian, Aditi Chattopadhyay

School for Engineering of Matter, Transport and Energy

Arizona State University, Tempe, 85287

Abstract

This paper presents a study in which carbon fiber composite plates constructed with multi-walled

carbon nanotube (MWCNT) reinforced epoxy are subject to various impact tests using a single

stage light-gas gun and 3D printed projectiles. Nanocomposites with varying MWCNT weight

percent (wt.%) values are primarily characterized to obtain the elastic mechanical response.

Additionally, gas gun impact tests at varying kinetic energy values would help provide further

insight to nanocomposite response under high stresses that may likely occur in commercial and

military applications. Delamination, cracking, and material failure from high velocity impacts will

be studied in this investigation.

I. Introduction

In recent years, nanoparticles and their possible applications have gained much attention from

researchers and the public alike. Carbon nanotubes (CNTs), in particular, have been lauded for

their excellent thermal, mechanical, and electrical properties [1]. CNTs possess a Young’s

Modulus on the order of ~1TPa, offer extremely low electrical resistance, and a thermal

conductivity approximately twice that of diamond [2]. Theoretically, the incorporation of CNTs

into a polymer matrix should drastically improve the properties of the host material, a carbon fiber

composite plate in this case. Although preliminary testing of nanocomposites demonstrates

promising results, widespread industrial implementation has not yet occurred dues to concerns

surrounding the ability to consistently replicate results on a large scale, commercial viability of

current production methods and a general lack of documentation of the characteristics and

properties of nanocomposites [1]. Therefore, it is critical to study the material response of

nanocomposites under various loading conditions.

Khan and Kim [3] published a review detailing the impact response of nanocomposites and

improvements that must be made for nanocomposites to have more widespread applications. The

authors address that the excellent in-plane characteristics of carbon fiber reinforced polymer

composites (CFRPs) have been well-documented, but also that out-of-plane, or “through-the-

thickness”, performance of CFRPs have proven to be poor in comparison. Less than ideal out-of-

plane properties in these composite structures may be a significant factor in their limited

implementation in industry.

Crack initiation and progression within interfaces between laminae are some of the greatest points

of weakness within composites. When these interfaces begin to fail, delamination begins to pose

a serious threat to the life and longevity of the composite structure and initial testing has suggested

that CNT addition assists in resistance of these failures. In attempts to better understand these

properties and address these concerns, studies including punch tests and low-velocity impact

testing have been conducted [3,4,5]. However, the comprehensive evaluation of high velocity

impact behavior of nanocomposites in ballistic environments will provide a better understanding

as to the limits of these materials and what may be done to improve them.

II. Characterization of Nanocomposite

There are several issues that must be addressed to ensure that finished composite fabrications are

uniform in material distribution and construction. One of the key factors that plagues CNT

utilization is difficulty reaching appropriate dispersion within a polymer matrix. Because of their

exceptionally large aspect ratio and strong intermolecular forces (Van der Waals), CNTs will tend

to agglomerate, entangle, and present alignment issues in a fluid [8]. In addition, during the

introduction of CNTs to materials such as epoxy for use in the construction of composite plates,

the formation of voids within the fluid must be avoided or else they will present as points of failure

in the final nanocomposite.

As such, various dispersion-aiding procedures have been developed to address voids,

agglomerations and entanglements. Ultrasonication, extrusion and various chemical methods have

proven to significantly aid in uniformly dispersing CNTs [8]. This study would ensure appropriate

dispersion of CNTs by use of a probe ultrasonication apparatus for a long period of time (1-2

hours) at low frequencies. Higher frequencies may disperse materials more rapidly, but also

introduce defects on the CNT surface, therefore mitigating the potential benefits of their addition

to a polymer matrix. As an added measure, a suspension fluid will be inserted and spread within

the mixture to aid in the uniformity of dispersion of CNTs within the final product. Additionally,

MWCNTs (as opposed to SWCNTs) will be used so that if a layer nanotube is damaged, there is

a buffer that will aid the health and survival of the CNTs. To lend credence to the results of this

study, several samples of nanocomposites will be analyzed using Scanning Electron Microscopy

(SEM) in order to verify that the CNTs were indeed suitably dispersed.

Furthermore, the mechanical properties of the nanocomposite will be correlated with degree of

dispersion by performing mechanical deformation tests on a dynamic loading frame. These tests

would help in the characterization of the elastic properties of the nanocomposite. Additionally,

further insight into deformation characteristics, damage initiation, and crack development could

be gained from these tests. Such insights would certainly prove invaluable when analyzing the

nanocomposites after high velocity impacts.

III. High Velocity Impact Testing

A single stage gas gun that has been thoroughly calibrated will be employed for the high velocity

impact study in the paper. A velocity profile has been developed for it to have predictable

velocity/kinetic energy values at predetermined compressed gas values using specific projectile

shapes and sizes. The system is composed of a gas cylinder connected to a sealed chamber (with

a mounted gas pressure) and barrel where a projectile is inserted. The projectile travels down the

barrel once the gauge reaches the desired pressure value and inhouse manufactured rupture discs

are melted by way of a current being applied to a nichrome wire. The effects of drag are

significantly mitigated by way of a vacuum that provides considerable negative pressure within

the barrel and impact chamber. The maximum recorded values for velocity and kinetic energy

achieved have been 764.6 m/s and 972.0 J, respectively. Design alterations for the gas gun are

currently being explored to reach 1000 m/s and ~1700 J.

Projectiles for the impact test will be 3D printed; this allows for the possibility of different

projectile leading edges meaning that initial points of contact with the specimen can be changed

(without significant change in projectile velocity since the system is in a vacuum), thereby

changing the manner in which energy is transferred to the specimen.

With all of these variables taken into account, the gas gun will provide consistent testing and allow

for effective testing of nanocomposite specimens. Variation of CNT wt.% across different

specimens promises a unique opportunity into how different weight fractions of CNT affect the

mechanical properties of the polymer matrix and at what point, if any, benefits begin to diminish

or even harm certain structural capabilities of the composite. It is expected that the addition of

CNTs to the polymer matrix will greatly enhance the structural integrity of the composite but at a

certain weight fraction, any greater addition will not have significant effects.

My introduction to the world of research was recent but I have found myself learning so much

more than I anticipated. Being first exposed to the promising work being done at the Adaptive

Intelligent Materials & Systems (AIMS) Center under Dr. Aditi Chattopadhyay and her group has

afforded me opportunities that have profoundly changed my life’s endeavors and made me reflect

on what I want to achieve.

INDUSTRY EXPERIENCE

This past summer, I started working as a Mechanical Engineering Intern at Northstar Aerospace.

I submit customer rework packages ($1500/ea) detailing defects/corrective actions from Material

Review Requests, particularly on Apache and Chinook helicopter transmissions. Over summer I

worked a minimum of 50 hours and sometimes did additional weekend shifts. I also Create

inspection/training documents to communicate Engineering’s blueprint/MOT changes to

machinists/inspectors and make corrections to technical drawings. I designed a First Pass Yield

system in VBA (Visual Basic for Applications) in Excel for the Director of Quality Assurance to

document all Inspection jobs to reduce package errors/correction time and to record error metrics.

Helped continuous improvement of processes by increasing parallel machining/reducing

inspection time on RATS (Ram Air Turbine Systems) manufacture. I assisted a Level III operator

in non-destructive testing (liquid penetrant, magnetic particle and radiography). Finally, I

contributed to a successful audit for AS9100D certification by correcting documents to meet export

control protocol.

INTEREST PAPER

My introduction to the world of research was recent but I have found myself learning so

much more than I anticipated. Being first exposed to the promising work being done at the

Adaptive Intelligent Materials & Systems (AIMS) Center under Dr. Aditi Chattopadhyay and her

group has afforded me opportunities that have profoundly changed my life’s endeavors and made

me reflect on what I want to achieve.

Prior to meeting the AIMS Center group and learning about their projects, I had a vague

idea of what I wanted to accomplish. I would complete the remaining classes required to graduate,

obtain an internship and likely begin working immediately after graduation at the firm I interned

at. However, the ideas, challenges and possibilities that I have encountered have encouraged me

to expect more of myself. I now intend to pursue a Master’s degree in Mechanical Engineering at

the least and am now also considering committing to a PhD program at the AIMS Center once I

complete my Master’s with Dr. Chattopadhyay. I believe that these advanced degrees will help me

develop a better understanding and to better contribute to work in the composite structures field.

Although I am still unsure of whether I want to stay in academia or if I will seek more commercial

prospects upon receiving these degrees, I do know that I would like to continue working with

materials however that may be.

The potential for FURI approval to aid in these efforts cannot be overstated. Several aspects

of the program, I believe, will provide tangible benefits in the furthering of what many may

consider lofty goals. For example, program funding would help legitimize my project to others

and allows for the purchasing of components to gather more data to better determine modelling

parameters and provide more insight into damage behavior of my composites. Additionally, this

would help begin a portfolio to document and demonstrate my capabilities within research to

design, pursue, and complete projects independently.

This project will allow to deepen my foundational basis and apply knowledge developed

from previous time in the lab and from courses taken at Arizona State University. As I continue to

take my major’s upper division courses and reach the end of my undergraduate career, I will learn

all that a Bachelor’s degree can offer me and will have had to develop a strong multifaceted

background in order to present myself as a viable and promising graduate candidate for the best

programs. FURI and all it offers presents a perfect opportunity to begin building the skillsets and

networks needed to result in the best possible outcome in the hopes of becoming a graduate student.

I would like this to be the first of several projects that I will complete in my undergraduate career.

Additionally, the rigor and novelty of my proposals will give me a chance to attend conferences

and events where industry leaders and renowned researchers will be present. As such, I want to

present my finding, learn from other presenters, and establish mutually beneficial relationships

with those who attend.

The field of carbon fiber reinforced polymers is a fairly new one. Further more, the

intersection of carbon fiber reinforced polymers is a field of study that has only just begun to be

explored in recent years.

Traditionally, impact tests have been confined to velocities under 150 m/s [4], 100 m/s [5] and low

kinetic energies (5 J) [6]. If CNT reinforced nanocomposites are to ever replace more traditional

materials in industry, the upper limits of the composites must be thoroughly understood and then

improved to reach parameters demanded by consumers. Past investigations have determined that

the impact damage mechanisms of CFRPs are strain-rate-dependent [5]. Therefore, while punch

tests may be assumed to be a useful analogue for ballistic events in some cases [5], subjecting

specimens to higher velocity impacts (and higher strain rates) allows for a better understanding of

this response. Impact tests ranging from 300-700 m/s provide a unique opportunity to study the

behavior of composites in more hostile environments and to verify whether previously recorded

properties hold true in harsher conditions. Additionally, high-velocity impacts may provide a better

model for real-world conditions these structures may experience, especially aerospace and military

applications.

Various CNT weight fractions have been proposed as a solution for maximizing out-of-plane

loading capabilities of nanocomposite structures. Previous studies have published results that

suggest different values for optimum CNT wt.%. Some papers have suggested ~2.0% [1,5], ~1.0%

[3], and ~8.0% [7] for maximum performance, among many others. It would be beneficial to

generate more data supporting a range of most benefit for CNT weight fraction. Aside from having

diminishing returns past a certain weight fraction of CNT, CNT addition has adverse effects in that

viscosity of a CNT mixture increases severely with even small amounts [3,5]. This increased

viscosity leads may greatly affect the ability of the CNTs to penetrate fibers [5] and may lead to

severe agglomeration [3]. As a result, dispersion of CNTs must be carefully monitored so that

stresses are optimally transferred to the structure for optimal performance.

The risk-reward assessment for this project is really quite simple. The approaches that are

and will be implemented are novel but related research along the same vein has suggested that

carbon nanotubes may significantly improve damage response to both the carbon fiber and the

polymer matrix within the composite. Therefore, risks are deemed to be fairly low as a result. The

rewards vastly outweigh the risks in this equation as the potential for next-generation

nanocomposites could greatly replace metals in nearly every case one day

More directly, this project concerns itself with the damage behavior of carbon nanotube

enhanced-carbon fiber laminate composites. Furthermore, the mechanical characterization

component of the nanocomposites is also a major aspect. These two facets of my first independent

project, first of all, serve as development in the many functions a researcher has to complete.

Beyond experimentation, a researcher has to be familiar with technical presentations,

administrative processes, manipulation of data and making conclusion derived and supported by

data obtained from experimentation. This project would be the first step upon which I would build

a career.

To me, this a very exciting endeavor, especially once I graduate and begin my own

independent projects once I begin the pursuit of a Master’s degree. It is exciting because I will

essentially be working three fields, all of which interest me. The carbon fiber polymers and carbon

nanotubes I work with are essentially testing and researching the materials’ mechanical properties

(for the scope of my project) which is one of the key facets of materials science. Additionally, I

hope to move to creating improved T-Joints which would fall into the realm of structures of

mechanical engineering. Finally, these structures are being built in the context of aircraft where

the T-Joints can be used to create spars and ribs that line the fuselage and wings of a plane.

I think this is a very exciting area of research because once I finish my graduate degrees, I

can quite easily transfer my knowledge and skills toward industry. I have actually spoken with

several engineers and they agree that this would be a valuable field to invest in. For example, at

Boeing, they highly value PhDs with a title they call technical fellows and an engineer I spoke

with from Rogers Corporation said that they have a division dedicated solely to the research,

development and implementation of carbon fiber structures.

As for preparation, I feel I am uniquely suited to begin a graduate level project given that

I have worked at the Adaptive Materials and Systems Center for close to two years now and the

relationships I have formed with my Principal investigator, graduate students and postdoctoral

researchers have afforded me a unique opportunity. I now know the process of applying to graduate

school and am planning on taking the GRE this coming Spring, although I have a unusual case

where I will be graduating next Fall instead of Spring. My principal investigator Dr.

Chattopadhyay has expressed wanting me to stay for graduate school but has not yet confirmed

any plans.

I have developed many skills while working at the AIMS Center. My skills primarily relate

to carbon fiber and composites research such as wet layup for carbon fiber construction and the

use of autoclaves, ovens and heat for unique shapes. Additionally, both of my research projects,

optimization of the gas gun and my study on high velocity impacts of nanocomposites have

allowed me to hone my skills in Design of Experiments and data collection. Lastly, I have used

statistical process control (SPC) to create and finetune the quality of my specimens to be extremely

uniform in order to ensure accurate results.

My future plans are really up in the air right now. I have one more summer left before I

graduate and I really want to make the most of it. I have interviewed with Northrop Grumman,

Boeing, Microsoft, Intel and have started to receive offers. I have accepted Intel’s offer of Process

Engineer Intern and will be working there starting this December until the end of the Spring

semester. I plan to use the skills I gain in electronics and consumer products to break into tech as

my experiences in aerospace (too much red tape/bureaucracy and slow changes to engineering

decisions) have left me wary of it. I have a Boeing offer for a Manufacturing/Production

Engineering Intern position but ultimately my greatest dream right now is working for Microsoft’s

Hardware Engineering Team in their devices group. I believe I should be hearing back this Tuesday

but it is extremely competitive and so the Boeing offer is my Plan B. As you can see, although I

will be taking the GRE soon, I am very interested in working in industry. I really enjoy research

and working to make new discoveries but I also want to start climbing the corporate ladder and

becoming a leader in the workforce. I really would like to pursue a graduate degree one day and

have the perfect opportunity at the AIMS Center but I think I am leaning to joining the workforce

upon graduation. This however, heavily hinges on whether I get an offer from Microsoft and what

my professor plans to have me working on.

High-Velocity Impact Assessment and Mechanical Characterization of Carbon Nanotube Embedded Composite

I. Abstract

In recent years, nanoparticles and their possible applications have gained much attention from researchers and the public alike. Carbon nanotubes (CNTs), in particular, have been lauded for their excellent thermal, mechanical, and electrical properties [1]. Theoretically, the incorporation of CNTs into a polymer matrix should drastically improve the properties of the host material, a carbon fiber composite plate in this case. Although preliminary testing of nanocomposites demonstrates promising results, widespread industrial implementation has not yet occurred due to concerns surrounding the scalability of results to the structural level, and a general lack of documentation of the characteristics and properties of nanocomposites [1]. Khan and Kim [2] published a review detailing the response of nanocomposites to impact loading and improvements that must be addressed. They identified the less than ideal out-of-plane properties in these composite structures to be a significant factor in their limited implementation in industry. Tensile failure of composite fibers, delamination tendencies and other phenomena all contribute to these poor characteristics and so nanofillers have been proposed as a solution, and their performances have been compared using impact tests. Traditionally, impact tests have been confined to low velocities under 150 m/s [3], 100 m/s [4] and low kinetic energies (5 J) [5] for nanocomposites. If CNT reinforced nanocomposites are to ever replace more traditional materials in industry, the upper limits of the composites must be thoroughly understood. While punch tests may be assumed to be a useful analogue for ballistic events in some cases [4], subjecting specimens to higher strain rates/impacts allows for a better understanding. To better understand the breadth of composite loading behaviors, this study will concern itself with high-velocity projectile impact tests on composite laminates, an area that previous studies have not yet explored. Post-impact results will be studied using damage assessment techniques, both numerical and visual, in order to compare the performance of neat composite plates and

nanocomposite plates with differing weight fractions of CNT. Additionally, several mechanical characterization methods will be employed with the aid of a dynamic loading frame.

II. Fall Tasks Impact tests ranging from 300-700 m/s will be conducted to study the behavior of composites in more hostile environments and to verify whether previously recorded properties hold true in harsher conditions. A single stage gas gun capable of reaching these velocities and appropriate projectile kinetic energies will be used to conduct these tests at the Adaptive Intelligent Materials & Systems (AIMS) Center laboratory. The maximum recorded values for velocity and kinetic energy achieved have been 764.6 m/s and 972.0 J, respectively. Neat (no nanofiller added) composite and nanocomposite will be tested at several kinetic energy values and then compared with regards to damage assessment. Several damage quantification techniques will be implemented in order to help understand how the plates react to ballistic events. One such technique is ballistic limit characteristics. The velocities/kinetic energies at which the steel projectiles begin to perforate the thickness of the plates and the values at which the projectiles completely penetrate the specimens are certainly valuable findings that will provide data to compare sample performance. A dynamic loading frame will also be used to perform tensile tests as a form of mechanical characterization of the neat- and nano-composite. The loading frame can create custom loading procedures which will be used to record axial load, strain, and time for each specimen. From this data, stress and strain can be calculated using the geometric data of each specimen. From the stress-strain curves, critical material properties can be gathered and documented such as Young’s

Modulus, necking, and rupture.

III. Spring Tasks Various CNT weight fractions have been proposed as a solution for maximizing out-of-plane loading capabilities of nanocomposite structures. Previous studies have published results that suggest different values for optimum CNT wt.%. Some papers have suggested ~2.0% [1,4], ~1.0% [2], and ~8.0% [6] for maximum performance, among many others. It would be beneficial to generate more data supporting a range of most benefit for CNT weight fraction as there are diminishing returns past a certain weight fraction of CNT [2,4]. As such, Spring semester will focus on optimizing nanocomposite performance by way of varying CNT wt.%. Tests are expected to demonstrate how different weight fractions of CNT affect the mechanical properties of the polymer matrix and at what point, if any, benefits begin to diminish or even harm certain structural capabilities of the composite. It is expected that the addition of CNTs to the polymer matrix will enhance the structural integrity of the composite but at a certain weight fraction, any greater addition will not have significant effects. It is also anticipated that there that damage phenomena such as spalling (entry diameter larger than exit diameter), petalling, and plastic deformation cones will be observed but with diminished effects on the nanocomposite samples. The analysis techniques employed in the Fall semester will once again be used with the addition of microscopy to better discern ballistic performance of the nanocomposites as they might perform very similarly and additional measures will have to be taken to ensure that conclusion regarding the optimum CNT wt. % are reasonable and reliable. Phenomena that will be specifically examined under a microscope will be the plastic deformation cone after impact, tensile failure of primary (directly experiencing impact) and secondary fibers, global damage and damage

localization, delamination and epoxy failure among others. The expected outcome is that composite plates with a low weight fraction of CNT will offer the best combination of dispersion and property transfer and thus the best structural performance and support the use of nanofiller as a solution to improve out-of-plane characteristics of composite laminates.

IV. FURI Research Theme Significance Of the five research ASU themes, this study concerns itself with security. Once the structural performance of nanocomposites is maximized and thoroughly documented, the potential to support national interests and public welfare is almost boundless. These materials can be used to reinforce buildings, construct vehicles and provide a foundation and surface for autonomous self-healing systems that monitor structural health of civilian and military platforms. This is in addition to all the weight savings compared to traditional metal materials and in many cases at a reduced cost and the relative ease of influencing geometry with the aid of a mold. More concretely, these materials could help improve ballistic resistance and tolerance in military aircraft and improve dynamic load performance in load-bearing columns to improve earthquake resistance in building to name some possibilities. Ultimately, the potential for nanofiller to improve composite characteristics presents an unprecedented advancement in materials with unparalleled capabilities.

References [1] Prashantha, K., Soulestin, J., Lacrampe, M.F., Krawczak, P., Dupin, G., and Claes, M., “Masterbatch-based multiwalled carbon nanotube filled polypropylene nanocomposites: Assessment of rheological and mechanical properties,” Composites Science and Technology, Vol. 69, No. 11–12, 2009, pp. 1756-1757. [2] Khan, S. U., and Kim, J., “Impact and Delamination Failure of Multiscale Carbon Nanotube-Fiber Reinforced Polymer Composites: A Review,” International Journal of Aeronautical and

Space Science, Vol. 12, No. 2, 2011 pp. 115-125. [3] Zamani, M.M., Fereidoon, A., and Sabet, A., “Multi-walled carbon nanotube-filled polypropylene nanocomposites: high velocity impact response and mechanical properties,”

Iranian Polymer Journal. Vol. 21. No. 12, 2012, pp. 887. [4] Tehrani, M., Boroujeni, A.Y., Hartman, T.B., Haugh, T.P., Case, S.W., and Al-Haik M.S., “Mechanical characterization and impact damage assessment of a woven carbon fiber reinforced

carbon nanotube–epoxy composite,” Composites Science and Technology, Vol. 75, Feb. 2013, pp. 42-44. [5] Yang, K., Gu, M., Guo, Y., Pan, X., and Mu, G., “Effects of carbon nanotube

functionalization on the mechanical and thermal properties of epoxy composites,” Carbon, Vol.

47, No. 7, 2009, pp. 1725. [6] Cai, H., Yan, F. and Xue, Q., “Investigation of tribological properties of polyimide/carbon

nanotube nanocomposites” Materials Science and Engineering, Vol. 364, No. 1-2, 2004, pp. 97-99.

FURI Budget Request Note: students are eligible to receive up to $400 per semester. You may request funding for 1-2 semesters.

Student Name: Aldo Soberon Faculty Mentor Name: Dr. Aditi Chattopadhyay

Spring 2017 Budget Request Item Expense Budget Justification

Helium Tank 2X100=200 Propellant for gas gun impact tests

Steel Sphere Pack (300 qty) 1X30=30 Projectile for impact tests

Multi-walled carbon nanotubes(20g)

1x50=50 Used to fabricate nanocomposite specimens

Nichrome Wire roll 2X10=20 Used to fabricate rupture disks for gas gun operation

Laser 1X100=100 Replacement for failing laser in velocimeter system

Total $400.00

FALL Aug. 17 – Sep. 1 DONE: Fabricate neat and 1 wt. % CNT

plates Sep.1 – Sep.8 DONE: Machine specimens from plates

Sep.8 – Sep. 22 DONE: Tensile tests Sep.22 – Oct. 6 DONE: High velocity impact tests Oct. 6 – Oct. 20 DONE: Visual deformation damage analysis Oct.27 – Nov.17 Formal writeup

SPRING

Jan.8 – Jan.22 Fabricate plates with 1-4% wt. CNT Jan.22 – Jan.29 Machine specimens from plates Jan.29 – Feb.12 Optimizing weight fraction for performance Feb.12 – Feb.26 Find ballistic limit of specimens Feb.26 – Mar.12 Microscopy/basic quantification damage

analysis Mar.12 – Apr.17 Formal Writeup

PERSONAL STATEMENT My introduction to the world of research was recent but I have found myself learning so

much more than I anticipated. Being first exposed to the promising work being done at the Adaptive Intelligent Materials & Systems (AIMS) Center under Dr. Aditi Chattopadhyay and her group has afforded me opportunities that have profoundly changed my life’s endeavors and made

me reflect on what I want to achieve. Prior to meeting the AIMS Center group and learning about their projects, I had a vague

idea of what I wanted to accomplish. I would complete the remaining classes required to graduate, obtain an internship and likely begin working immediately after graduation at the firm I interned at. However, the ideas, challenges and possibilities that I have encountered have encouraged me to expect more of myself. I now intend to pursue a Master’s degree at the least and am now also

considering committing a PhD program as well. I believe that these advanced degrees will help me develop a better understanding and to better contribute to work in the composite structures field. Although I am still unsure of whether I want to stay in academia or if I will seek more commercial prospects upon receiving these degrees, I do know that I would like to continue working with materials however that may be.

The potential for FURI approval to aid in these efforts cannot be overstated. Several aspects of the program, I believe, will provide tangible benefits in the furthering of what many may consider lofty goals. For example, program funding would help legitimize my project to others and allows for the purchasing of components to gather more data to better determine modelling parameters and provide more insight into damage behavior of my composites. Additionally, this would help begin a portfolio to document and demonstrate my capabilities within research to design, pursue, and complete projects independently.

This project will allow to deepen my foundational basis and apply knowledge developed from previous time in the lab and from courses taken at Arizona State University. As I begin to take my major’s upper division courses and reach the end of my undergraduate career, I will learn

all that a Bachelor’s degree can offer me and will have had to develop a strong multifaceted background in order to present myself as a viable and promising graduate candidate for the best programs. FURI and all it offers presents a perfect opportunity to begin building the skillsets and networks needed to result in the best possible outcome in the hopes of becoming a graduate student. I would like this to be the first of several projects that I will complete in my undergraduate career. Additionally, the rigor and novelty of my proposals will give me a chance to attend conferences and events where industry leaders and renowned researchers will be present. As such, I want to present my finding, learn from other presenters, and establish mutually beneficial relationships with those who attend.

More directly, this project concerns itself with the damage behavior of carbon nanotube enhanced-carbon fiber laminate composites. Furthermore, the mechanical characterization component of the nanocomposites is also a major aspect. These two facets of my first independent project, first of all, serve as development in the many functions a researcher has to complete. Beyond experimentation, a researcher has to be familiar with technical presentations, administrative processes, manipulation of data and making conclusion derived and supported by data obtained from experimentation. This project would be the first step upon which I would build a career.

November 4, 2018 Northstar Aerospace 401 South 36th Street Phoenix, AZ 85034 To whom this may concern: I am the Director of Quality Assurance at Northstar Aerospace and was the manager for Aldo since he began his internship here in May 2018. I assigned him tasks directly as well as gave him tasks received from program managers in the Quality Department and Engineering Department. Close to finishing his Aerospace Engineering undergraduate degree at Arizona State University, we have closely discussed his plans as he completes his tenure at ASU. He has received offers from Intel, Boeing, Northstar and is still in the midst of interviews. Naturally as an aerospace engineering major, he has interests in aviation and the defense industries but would also like to delve into the world of consumer products and microelectronics. This largely why he is applying to this Microsoft hardware engineering internship position. Aldo has always been ready to take on any task given to him and was never shy about beginning and completing assignments that he had little to no experience in. As the only technical intern at our firm, his workload is heavy. He has to designate his own task schedule, present deliverables and complete tasks from different departments. He was able to create a First Pass Yield system to capture metrics on every single part and assembly that went through Inspection using the Visual Basic programming language. He had little prior experience in this language yet was able to create a database with a simple user form to allow for quick and easy data entry. The automatic report system he included meant that all errors could be captured and that the time spent on recurring errors could be measured. As a result, these metrics could be used at production meetings to address package errors and to reducer overall lead times when shipping product. This was especially useful in reducing the amount of overdue product for Honeywell. In short, I believe his combination of skillsets in hardware and software, firm grasp of theory and tenacity make him an excellent candidate. Sincerely, Julio Mendoza Director of Quality Assurance Northstar Aerospace