ICMCTF 2012! - CD-Lab Application Oriented Coating Development

Pore-free CVD coatings resist acids and aggressive media.
Among other hard coatings Hardide fills the gap between thin film PVD
and CVD coatings, and much thicker rough and non-uniform thermal spray
coatings. Compared to thin PVD/CVD coatings, 50-microns thick Hardide
has higher load-bearing capacity and is much more durable in abrasive and
erosive applications such as oil drilling tools. Unlike thermal spray
coatings, Hardide gas-phase CVD coatings can be uniformly applied to
internal surfaces and complex shapes.
Hardide is an attractive replacement for Hard Chrome plating, which is
under pressure from the US OSHA and the EU REACH regulations, and is
especially suitable for coating complex shapes and internal surfaces.
Proven applications for Hardide coatings include critical parts of oil drilling
tools, aircraft components, and pumps and valves operating in abrasive,
erosive and corrosive environments, where the coating typically triples part
life.
10:00am G1-1-7 Improvement of the adhesion force between DLC and
polymers by CVD method with photografting polymerization, J.
Takahashi, A. Hotta (hotta@mech.keio.ac.jp), Keio University, Japan
Polymers, such as polyethylene (PE), polypropylene (PP), polystyrene (PS),
polyurethane (PU), polymethylmethacrylate (PMMA),
polydimethylsiloxane (PDMS), and polyethylene terephthalate (PET) are
widely used materials in various industrial fields. The polymers, however,
have low gas barrier property, low abrasion property and low adhesion
property. In order to solve these problems, diamond like carbon (DLC)
deposition with a new way of surface modification was introduced. Surface
modification is an important method for polymers because it can develop a
new function in the polymers through different types of substrates with no
loss in the bulk property, while still possessing simplicity and easiness in
the surface treatment. We focused on the DLC deposition by the chemical
vapor deposition (CVD) method and the photografting polymerization as
the surface modification. DLC can induce various functional properties due
to its high gas barrier property, abrasion resistance, biocompatibility, and
high chemical stability. It was found that the adhesive strengths of
photografted and DLC-deposited polymers were drastically increased as
compared with untreated polymers. In fact, the adhesive strengths increased
by up to 250 times after the photografting process. The photografted layer
effectively worked as an intermediate layer between DLC and polymers.
The photografting time only lasted for ~15-30 min. Additionally, the tensile
strengths of the bulk photografted polymers were also found remarkably
increased as compared with untreated polymers. It was therefore concluded
that the adhesion and the mechanical properties of polymers could be
substantially enhanced by the CVD method with the photografting
polymerization.
10:20am G1-1-8 Electrophoretic deposition of carbon nanotube films
on silicon substrates, A. Sarkar, D. Hah (dyhah@lsu.edu), Louisiana State
University, US
In recent years, electrophoretic deposition (EPD) process has been
envisaged as one of the convenient, low temperature and cost effective
solution-based techniques that produce carbon nanotube (CNT) thin films
on virtually any substrate. Some of the crucial application fields of
electrophoretically deposited carbon nanotube films are micro-electronics
and microelectromechanical systems (MEMS) technologies where silicon
substrates are used predominantly. However, the research and fabrication
trend of EPD of carbon nanotubes has been, so far, focused mostly on
conductive/metal substrates such as stainless steel, aluminum, nickel,
titanium and ITO (indium tin oxide)-coated glass plates. Published reports
on carbon nanotube coatings deposited by EPD on silicon substrates are
relatively few and thus it offers an interesting thin film research subject to
explore. In this study, EPD has been performed extensively to obtain
appreciable deposits of carbon nanotubes on silicon substrates with various
surface coatings. The process resulted in CNT film thickness up to ~15 µm
on metal-coated silicon samples from aqueous suspensions. In addition,
successful attempts in selective deposition and characterization of CNT thin
films by the subsequent EPD experiments on patterned metals atop
insulating layers like silicon dioxide and silicon nitride show compatibility
of this process with conventional silicon processes. Interesting phenomenon
of agglomeration of carbon nanotubes and subsequent degradation of the
CNT dispersed medium during the EPD process has also been observed.
The deposited nanotubes exhibited preferential deposition and adhesion
only on the metal surfaces even when the DC voltage was supplied to the
silicon substrate which was electrically isolated from the metal layer. The
observed deposition and adhesion of CNT films on the conducting surfaces
is attributed to both electrophoretic mobility of the charged CNTs in the
suspension and the hydrophilic interaction on the target surface. Deposition
of the nanotubes was confirmed by scanning electron microscopy and
Raman spectroscopy. Thickness of the deposited film showed a trend of
linear relationship to the electric field strength and the deposition
Wednesday Morning, April 25, 2012 58
duration.The results present great potential of CNT films for microelectronics
and MEMS applications.
10:40am G1-1-9 Implementation of Advanced Inorganic Coatings on
Military Aircraft, B.D. Sartwell (bruce.sartwell@osd.mil), Department of
Defense, US, G. Kilchenstein, Office of Secretary of Defense, US, V.
Champagne, B. Gabriel, Army Research Laboratory, US, M. Duffles, MDS
Coating Technologies Corp., Canada INVITED
Military aircraft must operate in significantly more demanding
environments and are often required to continue in service much longer than
commercial aircraft. Readiness and life-cycle costs associated with
maintenance are critical issues associated with weapons systems. This
presentation will provide information on the implementation of three
different inorganic coatings technologies that are having a major impact on
performance and cost reduction: (1) HVOF thermal spray coatings, (2)
Cathodic arc PVD coatings, and (3) Cold spray coatings.
The Department of Defense conducted extensive studies to qualify highvelocity
oxygen-fuel (HVOF) WC/Co or WC/CoCr thermal spray coatings
as a technologically superior, cost-effective alternative to electrolytic hard
chromium (EHC) plating which is widely used in manufacturing and repair
of aircraft components. EHC plating uses chemicals containing hexavalent
chromium, a known carcinogen. Because of the extensive use of EHC on
aircraft, separate efforts were undertaken to qualify HVOF coatings on
different categories of components including landing gear and engine
components. Results of materials and flight testing to qualify the HVOF
coatings will be presented. The Air Force is now implementing HVOF
coatings on most of its landing gear and they are designed for the newest
aircraft, the Joint Strike Fighter.
During aircraft operation, gas turbine engines are continuously exposed to
erosive media, such as sand and dirt suspended in the air, that is extremely
damaging to the compressor section of the engine, leading to reduced
performance and increased fuel consumption. Cathodic arc PVD coatings
consisting of a multi-layer ceramic metal matrix , developed by MDS
Coatings Technologies Corp., have been implemented on compressor
airfoils in the U.S. Marine Corps H-53 and CH-46 helicopters. These
coatings have accrued over 1 million operational hours in desert
environments, increasing engine reliability and lowering costs.
Research efforts in cold spray (CS) have shown it to be a promising
technology to impart surface protection to Mg and other alloy components
on helicopters and fixed-wing aircraft. Applications have been developed
by ARL, implemented into production, and have been incorporated into
such weapon systems as the B1 bomber and the UH-60 Blackhawk
helicopter. For the latter application, CS is in the process of qualification by
Sikorsky Aircraft Co. for use on the UH-60 to reclaim Mg components. The
CS repair has been shown to have superior performance, can be
incorporated into production, and has been modified for field repair, making
it a feasible method for recovering components, thereby reducing cost.
11:20am G1-1-11 The Wear behavior of Manganese Phosphate
coatings applied to AISI D2 steel subjected to different heat treatments,
S. Sivakumaran (ilaiyavel@svce.ac.in), Sri Venkateswara College of
Engineering,Pennalur, India, A. Alangaram, Sri Venkateswara College of
Engineering, India
This paper aim to investigate the wear behavior of manganese phosphate
coatings on AISI D2 steel after various heat treatments. Manganese
Phosphate is an Industrial coating used to reduce friction and improve
lubrication in sliding components. The change of hardness and
microstructure of AISI D2 steel at various heat treatments also observed.
The Surface morphology of manganese phosphate coatings was examined
by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray
Spectroscopy (EDX) .The wear tests were performed in a pin on disk
apparatus as per ASTM G-99 Standard. The wear resistance of the coated
steel were evaluated through pin on disc test using a sliding velocity of 0.35
m/s under normal load of 10 to6 0 N and controlled condition of
temperature and humidity. The Coefficient of friction and wear loss were
evaluated. The temperature rise after 15 min and 30 min were recorded for
each load. Wear pattern of coated pins were captured using Scanning
Electron Microscope (SEM). Based on the results of the wear test after
annealing of the manganese phosphate coating exhibited the lowest average
coefficient of friction and the lowest wear loss 60 N load.
11:40am G1-1-12 Deposition of low melting point metals by Cold
Dipping - Fluidized Bed Coating (CD - FBC), M. Barletta
(barletta@ing.uniroma2.it), Università degli Studi di Roma Tor Vergata,
Italy, A. Gisario, S. Venettaci, Università degli Studi di Roma La Sapienza,
Italy, S. Vesco, Università degli Studi di Roma Tor Vergata, Italy
In the present paper, the deposition of low melting point metals by Cold
Dipping - Fluidized Bed Coating (CD - FBC) is proposed. In particular,
medium carbon steel flat substrates were coated by dipping them in a