ALD for Non-Traditional Substrates: Continuous Flow-Through Spatial ALD on Fibers and Enhanced Corrosion Protection of Metal Surfaces

Session Notes:


ChristopherOldham, Ph.D. 

Researcher at NC State University




Atomic layer deposition (ALD) is finding new applications for forming thin film coatings on a range of substrates outside historical uses in the electronics industry. Emerging applications include applying coatings to temperature sensitive materials, such as polymers as well porous materials such as textiles or fibers for applications such as filtration, separations, catalysis, UV protection, and sensing. ALD for corrosion protection is also an emerging application for oil and gas as well medical devices. In this talk I’ll discuss some of our recent work in these emerging applications for coating textiles and protecting metal surfaces from salt corrosion.

0:00:03   Hello, everyone. My name is Chris Oldham. I'm from the Parson's research Group at N. C. State
0:00:09   University. Good morning. Good afternoon. Maybe good evening, depending on which part of the world
0:00:14   urine and watching this, whether it's live or on a recorded session. Today, I'm going to present a
0:00:22   talk on a O. D. For nontraditional substrates. I'm actually gonna break it into two smaller talks.
0:00:29   One talk is on work we've done with ailed de on fibers and a process with a flow through spatial ale
0:00:35   de tool that we developed for coding, fibers and flexible substrates. And in the second talk, I'm
0:00:41   going to talk about a lady for corrosion protection. I first want to thank the organizer's that
0:00:47   Forge Nano for putting together this summit, specifically Stacey and Mike for the technical
0:00:53   assistance and helping help. So with that, I'll get started with a talk. So on breaking this talking
0:01:01   to two different pieces of work that were supported by the National Science Foundation Foundation
0:01:06   and also to Navy contracts in collaboration with Calabasas Creek Research under the Navy S B. I in
0:01:13   our program.
0:01:17   So I'd like to introduce myself and a Parson's research group were from NC State University in
0:01:23   Raleigh, North Carolina. I've listed our website there. If you want to learn more information about
0:01:26   us, and in this talk I have pulled out a few names that are specifically people who helped
0:01:32   contribute to these pieces of work. I hope I haven't left anybody off, but there's a lot of people
0:01:37   have gone in to make this work what it is today, um, transferred over to a laser pointer.
0:01:43   Specifically, Greg Parsons is the P I and many postdocs but also now PhD re PhD graduate graduates
0:01:52   of the person's research group. So a little bit about myself to introduce. I joined the person's
0:01:58   research group as a co stock in Ah uh, 2011 and I manage many of the commercial interactions with
0:02:07   commercial groups, including working on many of our deal DIY projects with the Army and Navy. I
0:02:14   later worked as a senior researcher and served as a P I on several of our S P I. R. Programs that
0:02:21   we've had with different companies. I also worked as a P I on our Native culture barrier coating
0:02:26   program, where we work to provide on our deposit ultra barriers on flexible food packaging materials.
0:02:33   And currently, I'm a visiting scientist of the group spend my days working day to day full time as
0:02:40   president of a proposed technologies, which is a firm I founded with that works on a LG and working
0:02:45   with with other commercial groups on using L. D and commercial applications on our initial
0:02:51   commercial focus was working with a Libyan textile products. And now we work with all all sorts of
0:02:57   generally nontraditional substrates, uh, including silicon wafers. But things like, uh, these three
0:03:04   D parts like these carbon rings you see here
0:03:09   that I want to outline the talk for today for the this p l D some it. So I'm gonna give to talks.
0:03:15   The 1st 1 is on the continuous flow through a special L D process we developed for textile materials
0:03:21   and the 2nd 1 is enhanced corrosion, Protection of copper and salt environments with LD Single Layer
0:03:27   and Nana Limp nominate coatings. Now, for both of these talks, I put references here in case you
0:03:32   want to learn more papers that you can read more about this work since we're limited here on time
0:03:37   today.
0:03:40   So we're all here on a nail the summit. But some people here may not be as familiar with a lady
0:03:44   processing. I like to start with this slide and some of the benefits of a lady specifically for
0:03:49   three d orchestre architectures. You know, these highly useful for depositing highly confortable
0:03:54   coatings, as shown in these examples here on the right side of the image, uh, number two, you get
0:04:01   the ability to produce re reproducible film thickness or predictable film thickness generally on
0:04:07   almost any substrate. And in our work, we do this for applications on textiles. So I show this this
0:04:15   work here is one of our first pieces of work availed and textiles where we deposited nailed the
0:04:20   metal oxide coating on a nylon fiber. This is a cross sectional, my Crotone invention. When you see
0:04:26   the con firm polity of the l decoding, it's about a 10 centimeter coating on that name. Nine long
0:04:32   fibre. But these cuttings have also been deposited on other materials. And so where we were, our
0:04:40   interest in our group is using these materials a deposit on polymer substrates because they'll d a
0:04:46   Mike CBD offers the ability to deposit low temperature coatings and since many fibers or polymers
0:04:51   are thermally sensitive, we have the ability to do that. So here's another example here of of using
0:04:57   this process this ale de process, the deposit metal coatings are LD Tungsten coatings on nylon. What
0:05:04   we found in this process is is when we use seed. Layers of aluminum oxide were able to get good
0:05:08   tungsten coatings on these fibers. And without those sieg layers, we don't get good coveting. But
0:05:13   this is an uncoated nylon fiber here. So maybe that's in the first part of the talk. Our motivation
0:05:20   for special LD for fibers is is really related to developing processes that are faster than
0:05:27   traditional bachelor de traditional batch LD to date, eyes done in pancake tools or even said multi
0:05:34   way for tools. But the deposition rates are generally slow and require large amounts of equipment.
0:05:40   But for the textile industry, they don't coat things in batch for the coat things in continuous
0:05:46   manner, and they also need things to move fast. Step took the position rates, and so we were
0:05:52   motivated to develop a special L D process that could coat not only flexible substrates but textiles
0:05:57   and porous materials so these air. This is a process that we developed to flow reactive materials
0:06:04   through the fiber. And so there's many applications that we can use this for, including reactive
0:06:09   textiles like thes catalytic materials. We've developed in the past metal organic frameworks that
0:06:15   we've used A L. D. C. Layers to help grow in fibers but also Elektronik textiles, such as depositing
0:06:21   conductive touch sensors on fibers or things such as membranes or separation. So there's a lot of
0:06:27   applications here for a lady of fibers and textiles,
0:06:32   so a little bit further. Sodium polymers is important because generally the coatings provide minimal
0:06:38   damage to the polymers and you get very confortable thin film. So you can. You can play games such
0:06:44   as changing Hydrophobic City or the wedding properties from a very hydrophobic fabric to make it
0:06:48   very wedding. Additionally, you can put down those catalytic or reactive materials these metal
0:06:54   organic frameworks, such as I showed here you put a nail D. C. Later on a public propylene fiber.
0:06:59   This is a cross sectional tm image, and you can grow that organic framework on the outside of the
0:07:04   fiber. We've also done this work with Kevlar, where We've enhanced the mechanical resistance and
0:07:10   enhance the cut resistance on fibers. But there's many applications here from filtration, UV
0:07:16   protection, electronics, textiles, adhesion layers and wedding better. People have looked out and
0:07:21   are currently under investigation by different research groups.
0:07:26   Now I LD on polymers is not necessarily a straight through a Zale Dion flats or silicon wafers. Uh,
0:07:32   we like to think of LD on polymers is working within two growth regimes. The first here is hailed
0:07:39   the mechanisms of reactive surfaces. This is something that might mimic like a silicon wafer and a
0:07:45   comparable polymer that we might think about is celulas a cotton. So this is a cotton. This is a
0:07:51   substrate that has a wage groups where reactive monomers such as trying with aluminum, will react
0:07:57   very nicely with this substrate. So when starting with your polymer fiber, there might be some
0:08:02   heating expanding. But the team A will react with those ohh groups on the surface by dozing in your
0:08:08   water, you you grow and you conform. Very conform all thin films on that five or surface and you
0:08:15   could see here are some working doing that where you've got this very conforming hailed the aluminum
0:08:20   oxide layer on a cotton fiber depositions very similar to flat surfaces. But these are very complex
0:08:27   substrates with fibers and very tortures pathways. And you could say you could still get very
0:08:32   conform all coatings on these very complex substrates. Now the second growth mode is on a non
0:08:37   reactive surface. These air things like Polly properly, whether where the polymer backbone has no
0:08:41   reactive groups, so and starting the deposition will still be some expansion and heating the team A
0:08:47   will come in and try to react. But really, what happens is it infuses into the polymer backbone, and
0:08:52   depending on wind, you dose in your cool reactive. Into that cycle, you may get infusion and
0:08:58   reaction into the subsurface region so you'll start growing subsurface some of that palmer below the
0:09:04   surface region, and it'll grow both subsurface and begin to start growing on the surface, but really
0:09:11   rather roughened surface. And we've seen this through different nonreactive polymer species. But
0:09:17   this is probably properly and across sexual image of Polly probably coating the poly propelling with
0:09:22   aluminum oxide. You could see this the rough and fiber as compared to this cotton fiber that you get
0:09:27   from this this coded polypropylene, and this can lead to much rougher coatings and could also change
0:09:33   things such as your wedding properties. So in traditional batch L. D. Using things like this common,
0:09:41   viscous will reactor that used in many research groups. Batchelder. He's used where we separate the
0:09:47   precursors in time. And those the precursor steps Are you a suburb? I separated by the nerve gas
0:09:53   purge that might be nitrogen are organ, and those process steps are repeated over and over. Teoh,
0:10:00   where you cycle and you grow your film now and specially, would be instead of separating our speed
0:10:05   are precursors in time, but separate are precursors in space. So this is a kind of, ah, common
0:10:14   designed to a special. It'll be process where we have our purge called perch steps. But purge zones
0:10:20   better separated and they separate a precursor aimed precursor. Bree, where substrate will move
0:10:26   through. These precursors owns and they'll be repeated, or they'll slide back and forth through here
0:10:32   and grow our film back and forth in a, um, special process. Now, there's been many examples of
0:10:37   spatial de processes over the last many years. These include work from and this is for flat
0:10:44   substrates work from the George Group at UC Boulder, who developed a special It'll be process for
0:10:51   for wafer processing, but also Paul Putin. At T. You know who developed US rotational um, wafer
0:10:59   process, which then later led to spin outs of some of the special D companies that have come online
0:11:04   for the solar cell industry. And then, more recently, there's been work from Eric Dickie at Lotus
0:11:10   Apply Technologies, whose taking the same spaceship L D process but made it for flexible materials.
0:11:16   So he had this wind and unwind process that allowed you to put in flexible polymer materials into ah
0:11:24   ah coding tool, which has done at lower pressure. And then there was work done by Marcus Groaner at
0:11:31   a Lady Diana solutions, developing a kind of ah flexible Web tool that that cycled the Web
0:11:38   continuously over a under a coating head. And so these air very common examples that have been
0:11:44   demonstrating in the literature for flat for flat, not flat materials, but also but flat materials
0:11:53   that are have no porosity to me. So look that they've all been a tool that allows us to chorus
0:12:01   substrates and such as textile fibres. And so we call this a flow through a spaceship will be
0:12:06   process. Now it's a little unique to some of the other work that was done previously is This was
0:12:11   also done in atmospheric pressure because in designing the process for coding textiles and textile
0:12:16   process, everything's done. All coding has done generally at atmospheric pressure, so that was one
0:12:21   of our key design restrictions that were working with it. So here's the mock up of the initial tool
0:12:28   redesigned. What we have is ambient pressure on either side of the tool where the fabric is rolled
0:12:34   up on rollers and can go back and forth. And we have three deposition channels or zones. The Middle
0:12:40   Channel has has the ability to deposit three L D cycles between a t. M. A nature general water feed,
0:12:47   and then on each end, we have a nitrogen purge just to try to purge out any ambient water that may
0:12:53   come into the tool. But the fabric can come back and forth as many times as you want. You can build
0:12:57   up three L D cycles at a time, and this is purely for proof of concept. demonstration just approved
0:13:03   that textiles in an ale de toe at atmospheric pressure. So here's some solid works design of our
0:13:13   tool. And you could see what we have here is we have our main channels here of nitrogen water and tm
0:13:19   A. Those channels air fed down to further distribution channels. And these just distribution
0:13:23   channels are then fed down into this ale de cycle, the Sale de SAS channel right here. And so this
0:13:33   is the breakdown of the top you of that channel coming down onto the machine block. And then here's
0:13:38   the bottom view of how that looks where we have our nitrogen, purge our water message and purge tm a
0:13:45   metric and purge water and so on. Repeated in the fabric would slide underneath the back and forth.
0:13:51   And what's unique about this design, compared to others, is the precursor comes through and out and
0:13:56   has purged all gases pursed out from the back side here, and I'll show a little bit more from that
0:14:01   coming up. So here's a little bit more of that design and actually the specifics of of the machining
0:14:09   of each tool, and we'll tell you a little bit about the work that leads to this in our modeling
0:14:14   efforts. So this is the same The same the same block I showed earlier with a nitrogen shield on
0:14:20   either end and three L D cycles. And this is the block in the specific nozzle diameter that was made
0:14:27   in the specific requirements of the nozzles that came down here. So that you could see here is you
0:14:30   have many nozzles milled out through the channel, blocked better basically, um, flowing through
0:14:38   through the fabric and all the way through to the end of the bottom exhaust. There is some modeling
0:14:43   that we did before we started machining out this work. But what we're really, really interested in
0:14:48   doing in this work was, uh, deciding before we started machining what was the proper gap, spacing
0:14:54   and also the gas flow rate. And so what we're hoping for one of our goals with our design was did to
0:15:01   decide or figure out where we would get good separation of the precursors in the reactor design. So
0:15:07   what we found was larger gaps lead to larger Eddies, and we thought that might lead to more none.
0:15:12   This team more non uniformity is in the coding across the fabric substrate. So what we could see
0:15:18   here is reluctant Gaps have 0.4 millimeters one millimeter and flow rates from one SLM up to three
0:15:24   SLM and you could see generally we got good separation between our t m A. R purchase are purged zone
0:15:31   and are water under any of these conditions.
0:15:35   We're looking at this and the ending in the working at the gas will modeling. We see that as we look
0:15:43   at this modeling and each individual jet that comes through, we see as we increase the gas racing
0:15:49   the one millimeter and higher forwards we actually get mixing between, um that the the the water and
0:15:56   the nitrogen gas owns. So ultimately what we decided to work with was a gap of 0.4 millimeters and
0:16:03   flow rates up to three SLM because what we found was a smaller gap. Spacing and higher flow rates
0:16:07   and polluted improve the flow velocity across the substrate, then a wider spacing that leads of
0:16:12   Eddie's. And so in this design, we had to set the gap toe one height. It's not flexible, like other
0:16:20   designs, but that's what we used for our experiments here.
0:16:26   Here's the constructed tool here. We laid the tool up in an exhausted, ventilated cabinet to capture
0:16:34   any un reactive gases. For this was a design requirement of our agent s department. Just in case
0:16:41   there might be some, uh, let off of the tri metal aluminum inside the reaction zone. This is the way
0:16:48   that three channels are. We've got one channel here which isn't in our care zone another general
0:16:53   over here, which is another carrier zone. And then we're feeding nitrogen, Hear t May here and water
0:16:57   here. And I've got a video here that I hope will play. I changed my point. My laser pointer to a
0:17:04   regular.
0:17:07   See if I can get this to play. Okay, great. So here's the tool in operation. So we could see here is
0:17:13   we've got fabric that's rolled up on either end and that fabrics rolling through here between belt
0:17:19   speeds of 1 to 10 meters per minute. We can heat up this reactor zone between 2525 degrees Celsius,
0:17:28   and what happens here is I'll just play one more time. It says the boat comes through were flowing
0:17:32   precursor flow rates between continuous precursor flow rates between 50 and 500 s. CCM's at nitrogen
0:17:40   purge rates of two tennis limbs continuously, so you can see down here. We've got precursor exhaust
0:17:46   stones that pick up any gas that's coming through and in match transferred out to the house exhaust
0:17:54   switch back over to my highlighter.
0:17:59   What did we learn from developing this experimental tool? So as a demonstration case, we deposited
0:18:05   the Luminal B A, T M and water on polypropylene fibres at every actor temperature of 60 degrees
0:18:11   Celsius. So to do this, this is ah, one of our polypropylene fibres that has a GSM of 13.5 grams per
0:18:19   meter squared. And this is what it looks like. We rolled that are relayed that fiber inside of
0:18:24   rolled it up. And what we did is we would carry a silicon wafer monitor in with that fiber and you
0:18:30   see not to the silicon wafer here that stitched inside the fabric here just so we can monitor film
0:18:34   thickness. This is at the entrance of the wave of the reactor and they would carry through, back and
0:18:39   forth all the way through the reactor and back and forth, and then we would take measurements at
0:18:43   different spots along the fibre just to monitor film thickness and also show you wedding properties
0:18:50   of the poly propylene fiber. For initial testing, we looked at silicon substrates and a specialty
0:18:56   tool to just see if we're getting what we would expect linear growth as the number as we increase
0:19:02   the number of ale de cycles. What we found is we do get pretty much linear growth with some air on
0:19:08   our silicon wafers. Now what we do notice is that we're getting a higher growth rate in this tool,
0:19:13   about 1.5 instrument per cycle where typically a batch they'll be tool would deliver 1.1 instance
0:19:19   per cycle from an aluminum oxide process. Uh, now, as a control experiment, we ran TME only without
0:19:27   any water in a tool, and that leads to less than one nanometer growth over 99 cycles. So although we
0:19:33   have a slightly higher growth rate when we run team may only we see very little growth. So we we
0:19:39   believe we're getting good growth or good control over the growth and good control over that Miss
0:19:44   trick water inside the reactor. So this was our control to set up test
0:19:51   and fibers. It's very challenging to monitor how the how the fibers air coated it and what one
0:19:59   process we developed to monitor if fibers are coated was to look at the wedding properties of the
0:20:03   fiber. So this is a poly propylene fiber and what we find yours when we when we coat polypropylene
0:20:09   fibres at 60 degrees Celsius, there's a There's a very short wedding transition that happens right
0:20:15   around 55 degree or 55 cycles. And so we use this monitor here to see were recoding the poll
0:20:23   appropriate fibers in the same way that we do in a batch process. So here's our control coating the
0:20:30   same wholly appropriate fiber and our batch tool on Apollo appropriate substrate, and we see where
0:20:35   the top of the bottom we generally see that what entrances should happen right around 55 cycles of
0:20:42   aluminum oxide process sort of to in comparing the batch versus the spatial il de process we see in
0:20:51   a batch process, we get this wedding transition right around 55 cycles, as they showed in the
0:20:55   previous slide and in the special process. We also see this wedding transition Now what we do see,
0:21:01   is there some wedding variability? And so this may be from, uh, you know, uneven coating across the
0:21:09   fiber or some other non uniformity that are in a process that we haven't quite worked through. But
0:21:14   generally we see very good the same wedding transition that we found with our with our batch NLD
0:21:19   tool.
0:21:21   And one thing I'd like to make a note of is is in comparison with speed. We find that in our batch
0:21:26   LD tool, it takes about 1.5 hours to run 99 cycles or deposit the same coding and in our in our
0:21:35   specialty toe takes 1.5 minutes. So this is really the reason, the ultimate motivation of why we
0:21:40   want to use special D for cutting textiles and a commercially apply applied process. When we look at
0:21:49   the gas for rates, we see as we vary the team and hold the water, we get saturation, writes a
0:21:56   saturation around 50 s ccm's of T m a and then what we find as we increase as we vary the water and
0:22:05   hold the tm a. We see that increase in the team a float rate create somewhat of a CBD growth rate on
0:22:12   the back of the fabric, and we can weaken very are monitor our weaken weaken vary that by our
0:22:20   control some of that through an exigent flow rates.
0:22:25   We looked at our effect of our fabric Web speed. We see that decreasing a Web speed from 3.8 meters
0:22:32   for minutes of 1.6 meters per minute actually increases the residents time and allows more time for
0:22:37   the precursor to fuse in the fibers and ink. You know, speeds up that women transition potentially
0:22:43   were depositing a thicker coating there. And that's why we're seeing that wedding tradition happen
0:22:47   faster, uh, further as we, uh, and we also looked at the effect of the perpetrate on these inside
0:22:57   the tool we see as we increase the perjury. There's really no real change in the ah in the winning
0:23:07   properties of the fabric
0:23:11   and characterizing the fibers that were coded from this process. We we can't we analyze them with
0:23:17   their anywhere from zero cycles up the 450 cycles, and we could see around 42 cycles. We start to
0:23:22   see coding. There's actually some cracking here on these fibers and it's more apparent here. And we
0:23:27   actually see some particle buildup on the fibers as we increase the coating on top of the fibers.
0:23:33   Well, we do es analysis. We can see both aluminum oxygen signals pick up from the fibre man at just
0:23:40   99 cycles and tm cross sectional micro tome images of the poly probably in fiber of This is the
0:23:47   fiber interface here with epoxy. And you can see this black darkened region Here is the aluminum
0:23:52   oxide coating on the surface and it gets a little thicker here with, um, increased number of cycles.
0:24:01   So we find with this process we get visible coating around 42 cycles. Particulates begin to form
0:24:08   somewhere around 60 cycles that are not found on the batch coded samples. But the coating is found
0:24:13   to be uniforms so potentially around through the process. We're getting some sort of CBD effect that
0:24:19   could be that the fabric is coming out to the atmosphere and bringing back in some moisture that's
0:24:25   increasing. Are the monoxide growth on the surface potentially through some further control? On the
0:24:31   outside, ambient we would be outed lesson that particle build upon the fiber surface. But overall,
0:24:37   this is a good a good demonstration of our of the ale decoding process on fibers in a continuous
0:24:44   process. Further, we functional ized are re coated fibers and in this continuous process to
0:24:51   demonstrate, uh, promotion of functional ization of these moth him off materials we know from past
0:24:58   work when we take a poly propylene fiber coated with a thin aluminum oxide coating that been
0:25:03   aluminum oxide coating promotes metal, organic framework, arm off growth on fibers. So we get thes
0:25:09   catalytic materials, which can grow fibers. And so we demonstrated that here coating fibers through
0:25:14   this process. With 99 cycles, we see a little bit of off beginning to grow, but it's really
0:25:20   splashing into some some. It's non homogeneous, the growth on the fibers. But as we increased the
0:25:27   thickness to about 40 to 50 nanometers, we start to get very good uniform growth of the fibers, just
0:25:34   as we wouldn't are batch LD process that we demonstrated in lots of previous work.
0:25:41   But in summary, I think a show that just say that this is a good proof of concept design of an
0:25:46   atmospheric pressure, spatial be process for porous materials. We've investigated about the progress
0:25:52   of flow rates per speed and Web speed, but also looked at different polymer functionality. And we
0:25:58   looked at that permitted permeability, which I didn't talk about here. And there are some challenges
0:26:04   I mean, work through in the future. But if you'd like to learn more, we've got we've got a a
0:26:08   publication on this work and J b S t. So I'd like to move quickly into some work that we did on
0:26:14   corrosion protection of copper and salt environments for L D single there, Nan 11 It coatings. This
0:26:19   work was done in collaboration with the U. S Navy and Calabasas Creek Research into their S P I. R.
0:26:24   Program. Sorry about that. Here's a proof of concept coating. This is a traveling wave to T w T
0:26:33   electron collector that we've coated the internal components. But also here's the Here's an example
0:26:39   apart. And also here's a Sillen wade from a traveling wave to which is part of the radar system. And
0:26:45   the problem with this is the failures over the verdict. So some of the system requirements are there.
0:26:51   Specter running pure d i water, but on the boats. Often salt water breaks into their water skids, so
0:26:58   the contaminants get inside that cause corrosion that leads the Occident corrosion build up inside
0:27:03   the tubing that provides clogging. And then that leads to uneven heating in our of sources and
0:27:08   increased flow rates, which then leads to premature failure. And these devices are supposed to last
0:27:12   tens of years, and they last often only two years at a time. So there's a need also in the coatings.
0:27:18   If you can find one that's a bear according to preserve the electrical and thermal conductivity,
0:27:23   there can be no other Halloween or other protection inside. So Barry coding, specifically ultra thin
0:27:29   film barrier coatings, can preserve the system properties of the metal surface while retaining out
0:27:34   high electrical and thermal conductivity of the copper. So so L. D. Barry coatings are a very
0:27:40   promising piece of work that has been demonstrated recently. Metal oxides are nerve to make good
0:27:47   corrosion barriers. The coatings are very energetically favourable, specifically luminant titania.
0:27:52   But two issues are, you know, the loom in it can deposit very smoothly on the surface, but it could
0:27:56   be slightly soluble. Even in neutral water. You too, could be more stable, but it doesn't always
0:28:01   nuclear well in many surfaces and could be very roughest. Seen from these A F images images here,
0:28:06   which then ultimately doesn't protect the underlying substrate. So a promising solution that we've
0:28:12   recently found this half me. It's a common ale de material used throughout the electron ICS industry,
0:28:17   and it shows pretty good stability and water. So I'm gonna show some work from these three materials
0:28:21   to the our experimental set up is replied these three materials in single Nantel. It animate
0:28:26   configurations that the native news were applied at a time and the coatings were applied at less
0:28:31   than 200 degrees Celsius. They were investigated by E s and flow through liquid tube corrosion set
0:28:37   up. But I'll show you in a minute. Here's a demonstration of that, uh, electron collector that I
0:28:43   showed just a minute ago. The coding went in and coated inside all these channels. What we did is we
0:28:48   notched out a little part of this to see if it was coated in which you could see is this coating was
0:28:52   all along the copper surface of this electron collector.
0:28:58   So again, we deposited many material configurations. To look at this all deposit 150 degrees C up to
0:29:05   15 80 meters a coating thickness. Uh, this publication here goes into more detail about this work.
0:29:12   I'm going to skip over some of the electric chemistry work that went into deeply telling that
0:29:15   materials publications show here in our yes testing, we coated copper coupons, uncoated copper and
0:29:23   with different material combinations. And what we found was the aluminum oxide containing films
0:29:28   should degradation. The T 02 single layer coatings were nearly constant low frequency appearance,
0:29:34   but in general, behalf near and half Mia Titania. That's the H T times 10 as a 2.5 nanometer times
0:29:40   2.5 nanometer cycle 10 times Those show good stability in water and salt environments Assault being
0:29:48   appoint one Mueller Salt Solutions. So for coating tubing, we built this set up where we had our ale
0:29:55   de precursor manifold. We would line up copper tubing and then exhausted back out to the pump
0:30:02   exhaust. And this is our Senate for cutting the internal components of tubing. This is, ah, typical
0:30:09   tubing that we have set up for braise. It's got a gold copper braise or a silver copper brace filler
0:30:15   that's here. And this is generally what the Navy is concerned about with corroded surface that flows
0:30:21   apart. Our flow rate to these tubes was three meters per second, which which is a turbulent flow and
0:30:27   is the same type of flow that goes through their coin channels. We wanted to simulate the same
0:30:31   tension flows that the coin channel C on a navy. This is our life test set up. We would set up some
0:30:38   copper tubes here pump 0.1 molar solution 0.1 a salt solution through these tubes continuously over
0:30:45   different periods of time. This is inside of that bucket. And then ultimately, after the test, we
0:30:50   would notch out and look inside these both optically and by other microscope techniques. So this is
0:30:57   with the I water. Only this is our uncoated tube. This is with the aluminum oxide. After three weeks
0:31:02   in D. I water, this is half new and t 02 and you see the half nude just, you know, Christine, it's
0:31:08   basically but you see no changes to the surface properties there of the half year coated surface.
0:31:14   Now in the 0.1 Moeller salt solution. After three weeks, you can see the half. Nia coding is the
0:31:19   only one that generally survives the the the coating exposure to the salt solution. Now, comparing
0:31:28   the uncoated copper and 1/2 of this is that coated surfaces you can see they're pretty much the same
0:31:34   on then as well. For 14 days we see the capo are the happening coated copper surface and the brazel.
0:31:41   A joint looks good. No signs of corrosion. We're starting to see oxide corrosion build up inside the
0:31:46   copper circus after 11. And then as we increased from 21 days of the 56 days, the half nia coated
0:31:53   surface basically remains unchanged. Further as we take these from zero days, two weeks, three weeks
0:32:01   on up to eight weeks, the half name coated. Uh uh, Braised joint copper surfaces look almost
0:32:08   pristine after exposure to the salt solution. So these air very proud. Um, so, in summary, for the l
0:32:15   d corrosion barriers, we deposited 50 nanometer ale de thin film coatings for corrosion protection.
0:32:20   A copper specifically for tube interiors. Testing revealed degradation of alumina. That was someone
0:32:26   expected from the literature T I 0 2.5 men and eliminate coatings show promise in this application,
0:32:33   but further flow testing and 1/2 nail de coatings, they retain their surface properties. You mean
0:32:38   after 56 days in 560.1 Bowler Salt Solutions, which is a marked improvement both in D i water and
0:32:45   the salt solutions. So what? That I could wrap up and just thank you. I'd like to think the Parson's
0:32:50   research group and specifically all these members of the person's research group which helped
0:32:55   contribute to this work. If you'd like to learn more, please contact this through a website. I've
0:33:00   also list my email here. I love to hear from you and thanks for giving me the time today during
0:33:06   appeal, the P. A. L. D summit.