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penn State _ 

$ARL 

Institute for Man 



(lU.S. Navy Nonufocturinq 
Technoloqq Center of Excellence 



0 U H II T E R L V 




Focus On 
Materials Processing 


Gear Repair Project by Super Finishing Process 
Nearing Completion 

iMAST recently completed an end-of-project meeting to present the final results of 
its Navy ManTech gear super finishing program effort. Attending the meeting were 
representatives from NAVAIR, Boeing, and the U.S. Army. 

Large quantities of aircraft gears are currently scrapped at Navy Fleet 
Readiness Centers (formerly Naval Aviation Depots) in the routine process of 
helicopter transmission overhaul. Annual acquisition costs for replacement of these 
gears at Fleet Readiness Center (FRC) East at Cherry Point, North Carolina (for the 
CH-46 Sea Knight alone) is estimated to be over $3 million dollars. This project was 
initiated to demonstrate that a large portion of these “scrap” gears can be repaired 
and recycled back into their respective aircraft, resulting in a significant cost 
avoidance. 

The repair process identified by iMAST was the Isotropic Super 
Finishing (ISF) Process developed by REM Chemicals, Inc. of Brenham, Texas. 

This process has been found to be capable of uniformly removing very thin layers 
(0.0001 to 0.0002 inch.) of material from the tooth surfaces of hardened aircraft 
gears. 

During the fleet overhaul process, it is policy to scrap transmission 
gears that have minor FOD or micro-pitting surface damage due to corrosion 
and fatigue. Removal of the surface damage on these gears, however, using the 
ISF process, has shown that the number of actual gears being scrapped can be 
significantly reduced. Process results identified by iMAST have proven a large 
number of these gears can be returned to service within Original Equipment 
Manufacturer (OEM) gear tooth geometry, dimension and metallurgical 
specifications. 

A preliminary analysis of scrapped CH-46 “Mix box” gears received 
from ERG Cherry Point suggested that over 50% of the gears could be salvaged 
using the ISE process. The preliminary analysis also established a five-year (present 
value) Return on Investment (ROl) of 5.9, based on repairing only 4 out of the 20 
gears in the fore and aft transmissions of the CH-46 Sea Knight. In order to establish 
the feasibility of this repair process, scrap gears repaired by the ISF process were 
scientifically evaluated for gear strength and durability. The performance of these 
gears, as compared to the strength and durability of new gears procured from the 
approved Navy vendor, was shown to be very promising. 

Test rigs and fixtures at iMAST/ARE Penn State were specifically 
designed and built to accommodate the spur pinion and the collector gears pair 
of the CH-46 Mix gear box. New spur pinions and collector gears were acquired 


Continued on Page 7 


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Prescribed by ANSI Std Z39-18 





PENN STATE _ 

^iNAST 


Applied Research Laboratory 
Institute for Manufacturing and 
Sustainment Technologies 


DIRECTOR, IMAST& 

NAVY/MARINE CORPS REPAIRTECHNOLOGIES 

Timothy D. Bair 

(814) 863-3880 tdbl4@psu.edu 

MATERIALS PROCESSING TECHNOLOGIES 

Timothy J. Eden, Ph.D. 

(814) 865-5880 tjel@psu.edu 

LASER PROCESSING TECHNOLOGIES 

Richard R Martukanitz, Ph.D. 

(814) 863-7282 rxm44@psu.edu 

ADVANCED COMPOSITES MATERIALS 
TECHNOLOGIES 

Kevin L. Koudela, Ph.D. 

(814) 863-4351 klkl21@psu.edu 

MANUFACTURING SYSTEMS TECHNOLOGIES 

Mark T. Traband, Ph.D. 

(814) 865-3608 mttl@psu.edu 

SYSTEMS OPERATIONS AND AUTOMATION/ 
COMPLEX SYSTEMS MONITORING 

Eddie C. Crow 

(814) 863-9887 eccl@psu.edu 

DRIVETRAIN TECHNOLOGIES 

Suren Rao 

(814) 865-3537 sbrl@psu.edu 

iMAST ADMINISTRATOR and EDITOR 

Gregory J. Johnson 
(814) 865-8207 gjjl@psu.edu 

STAFF ASSISTANT 

Shannon Ranio 

(814) 865-3264 srrl2@psu.edu 

WORLD WIDE WEB 

www.arl.psu.edu/capabilities/mm_imast.html 

NAVY PROGRAM MANAGER 

Greg Woods 
(703) 696-4788 
woodsg@onr.navy.mil 


©2007. The iMAST quarterly newsletter is published by the Institute 
for Manufacturing and Sustainment Technologies of the Applied 
Research Laboratory at Penn State, University Park, Pa. iMAST is 
sponsored by the U.S. Navy Manufacturing Technology (ManTech) 
Program, Office of Naval Research, under Navy Contract N00024- 
02-D-6604. Any opinions, findings, conclusions, or recommendations 
expressed in this material are those of the authors and do not 
necessarily reflect the views of the U.S. Navy. Send mail list requests 
or address corrections to: iMAST Administrator, ARL Penn State, 
RO. Box 30, State College, PA 16804-0030 or e-mail: srr 12@psu.edu 
Parcel delivery address (UPS, FedEx, USPS): N. Atherton St. Rear; 

Research Building West, State College, PA 16804. 

Penn State is an equal opportunity/affirmative action university. 

This publication can be made available in alternative media on request. 

U.Ed.ARL 07-01 

IN THIS QUARTERLY 


Feature Article.3 

Institute Notes.7 

Calendar of Events.8 


DIRECTOR’S CORNER 


My Welcome Aboard 

Just before Thanksgiving my boss came into my office, with his hand extended, 
to offer me the iMAST directorship and say congratulations, 
in the same breath. He assumed I wouldn’t hesitate and he 
was right. 1 am proud to officially be a part of the ONR Navy 
ManTech team. Since retiring from the Air Force, continuing 
a life of service to our nation and the DoD has been my 
primary ambition. ARL Penn State and iMAST provide me an 
opportunity to continue making a difference. 

Now, what can you expect of the new director? I’ve 
spent the last three months, as the interim director, with a constant sense of 
awe as I’ve observed the ManTech program office operate. The contributions 
of the various centers of excellence and our own staff here at iMAST make 
me proud. The impact is inspiring, albeit a little intimidating from my initial 
perspective. This group has a sense of patriotic fervor that is centered on 
supporting the Sailor and Marine. 1 hope to help. 1 also plan to work hard over 
the next six months in three primary areas: 

1. Meeting and getting to know the players, programs and 
infrastructure is my top priority. 1 hope to make up for what my fellow (prior 
DoN) co-workers call "shortcomings” by visiting as many shipyards. Navy and 
Marine Corps depots, appropriate OEM facilities. Navy Labs, and program 
management offices as is humanly possible. 

2. 1 will be looking internally at our business practices with the intent 
to improve our efficiency and put more funding on the line for hands-on work. 

3.1 hope to significantly increase the amount of collaborative effort 
we support with the other Navy ManTech centers of excellence, government 
depots. Navy labs, and contractors. ARL, as the host of iMAST, has expertise in 
many different technologies that can be used synergistically with other centers 
to improve mission capability and support. 

The neatest thing about this new job is iMAST’s dual impact mission. 
Navy ManTech projects are, by definition, affordability- centered. iMAST is 
dedicating dozens of man-years effort to help the Navy acquire more ships 
— faster, better and cheaper. The impact of our contribution will be felt by 
Sailors 50 years from now. RepTech projects typically impact the logistics and 
maintenance personnel, military and civilian at all three levels, in the near 
term. The projects that iMAST supports make our Sailor’s and Marine’s lives 
a little easier today by improving the operational availability of their weapons 
systems in support of our national security priorities. 

As always, if you have ideas that can better help us accomplish our 
mission, please don’t hesitate to give us a call. We are proud to serve our men 
and women in uniform. 

Ohn Bmh. 

★ ★ ★ ★ 

MATERIALS MECHANICAL DRIVE LASER COMPLEX SYSTEMS 

PROCESSING TRANSMISSION PROCESSING MONITORING 

TECHNOLOGIES TECHNOLOGIES TECHNOLOGIES TECHNOLOGIES 

'k 'k 'k 

ADVANCED COMPOSITES NAVY/MARINE MANUFACTURING 

MATERIALS CORPS REPAIR SYSTEMS 

TECHNOLOGIES TECHNOLOGIES TECHNOLOGIES 



2 


2007 No. I iMAST Quarterly 








FEATURE ARTICLE 


Focus on Materials Processing 

Progress in High-Velocity Particle 
Consolidation Technology 

by Timothy J. Eden, Ph.D. 


Gas Heater 



Figure I. Schematic of the High Velocity Particle Consolidation Process. The process is robot controlled. 


The Materials Processing Division 
of the Applied Research Laboratory 
has been conducting research and 
transitioning technology for the 
past decade. A brief review of the 
High Velocity Particle Consolidation 
Process (HVPC) along with progress 
and current efforts will be presented 
in this article. 

High-Velocity Particle 
Consolidation (HVPC) is the process 
of applying metal and composite 
(metal/ceramic) powders on to a 
substrate by accelerating to velocities 
ranging from 400 to 1000 m/s. Upon 
impact the metal particles deform and 
bond with the substrate. Particles 
continue to impact the surface 
bonding with the already deposited 
particles building up very dense 
coatings. The deposition rate for the 
HVPC process can be as much as 15 
kg/hr or higher. The technology was 
developed in the middle 1980s at the 
Institute of Theoretical and Applied 
Mechanics of the Siberian Division of 
the Russian Academy of Science in 
Novosibirsk [1]. The technology was 
later patented in the United States in 
1994[2]. The HVPC is widely used 
in Europe and is gaining acceptance 
in the United States[3]. The process 
is also known as Cold Spray, Cold 
Gas Dynamic Spraying, Kinetic 
Metallization and Supersonic Particle 
Deposition. 

The basic HVPC process 
is shown in Figure 1. In the HVPC 
process, a compressed gas, usually 
nitrogen, helium or air is expanded 
through a converging/diverging 
or DeLaval nozzle to supersonic 
speeds[4,5]. Powder is introduced 
into the gas stream slightly upstream 


of the converging section of the 
nozzle. The expanding gas rapidly 
accelerates the particles to velocity 
sufficient to build up a coating. A 
gas heater is used to increase the gas 
temperature which results in higher 
gas velocities. This also increases the 
particle velocity and temperature to 
improve the deposition characteristics 
of the powder [6]. The particle 
temperature remains well below 
melting temperature of the particle. 
The substrate temperature remains 
below 150°C greatly reducing or 
eliminating any adverse thermal 
affects. There is no increase in the 
oxide content in the coating and in 
some instances the oxide level in the 
coating is less that the oxide content 


of the starting powder[7]. These 
characteristics make HVPC an ideal 
coating process for select applications 
such as the application of corrosion 
and wear resistant coatings. 

Advances in nozzle 
design, process optimization and 
powder processing have lead to 
the ability to deposit very dense 
coatings using the HVPC process. 
Aluminum, aluminum alloys, copper, 
stainless steel and nickel have 
all been deposited with densities 
greater that 99%. The HVPC process 
also produces excellent material 
interaction at the coating/substrate 
interface. An example of the unique 
microstructure and coating/substrate 
interface that can be produced by 



PROFILE 

Timothy J. Eden is a research associate and head of the materials processing 
department in ARL Penn State’s Materials and Manufacturing Office. Dr. Eden 
received a B.S. in mechanical engineering from the University of Utah, and an M.S. 
and Ph.D. in mechanical engineering from The Pennsylvania State University. Dr. 
Eden’s research interests include high velocity particle consolidation, spray metal 
forming, multiphase heat transfer and fluid flow, process control and optimization, 
ceramics processing, and thermodynamics. He can be reached at (814) 865-5880, 
or by e-mail at <tjel @psu.edu>. 


iMAST Quarterly 2007 No. I 


3 














































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-i 


-"a: ci 

1 


; A1-606T 


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1 . 

, ■, . ' ' 50 Jim 


Figure 2. Micrograph of Copper powder 
deposited on AI-6061. The mixing of the materials 
at the interface is clearly visible.[7] 



Figure 3. SH-60 HelicopterTransmission Gearbox 



Figure 4. Corrosion on Gearbox 

HVPC process is shown in Figure 
2 [7]. The substrate is Al-6061 and the 
coating is copper powder. The coating 
is 99.9% dense. As a result of the 
process, the high velocity particles are 
subject to severe amounts of plastic 
deformation. This plastic deformation 
can also occur in the substrate as 
well. The result is a coating/substrate 
interface where there is mechanical 
mixing of the material that is free of 
voids and inclusions. The extent of 
the interfacial mixing is dependent on 
the coating/substrate material system. 

Improvements in nozzle 
design have lead to higher deposition 


velocities and the ability to deposit 
larger particles. Gas dynamic models 
were used to design nozzles that 
can substantially increase particle 
velocities[8,9]. Increasing particle 
velocity results in denser coatings 
and higher deposition efficiency. 
Increasing the length of the nozzle 
from 83mm to 211mm, with nitrogen 
as the carrier gas, the calculated 
velocity of a 12pm copper particle can 
be increased from 553m/s to 742m/s. 
This is a 33% increase in particle 
velocity. The increased velocity 
leads to an increase in the deposition 
efficiency from less than 10% to close 
to 80%. There are fabrication and 
material constraints that limit the 
practical length of the HVPC nozzles. 
Other nozzle improvements include 
the use of new materials to improve 
powder flow through the nozzle and 
design optimization to minimize the 
gas flow through the nozzle. 

One of the frequently 
asked questions is how does the 
cost of applying coatings with the 
HVPC process compare to the cost 
of applying coatings using other 
thermal spray processes. To address 
this issue, the software package 
Cost Analysis Software (CAS) was 
developed to accurately calculate 
the cost of applying a coating using 
the HVPC process[10]. Code inputs 
include the cost of the powder, gas, 
and electricity, nozzle dimensions, 
carrier gas, powder mass flowrate, 
substrate dimensions, deposition 
efficiency, desired coating thickness, 
start up and shut down times, and if 
desired, labor, burden and equipment 
amortization. The output includes 
cost by category (gas, powder, labor, 
burden, amortization), cost per unit 
area, spray time, and the number 
of passes required to achieve the 
specified coating thickness. The 
CAS can also be used to determine 
deposition efficiency given the 
process parameters. The CAS was 
calibrated through experimentation 
and on the Navy Mantech 
Project C0934 AAV Enhanced 


Applique Armor Kit (EEAK) 

Product Improvementlll]. It was 
demonstrated during this program 
that the HVPC process was cost 
competitive with wire-arc spray for 
the deposition of aluminum on steel. 
Euture plans for the CAS include 
developing modules for complex 
geometries and to predict the cost of 
other thermal spray processes. 

The current ManTech 
program involves the development 
of corrosion resistant coatings for the 
magnesium gearboxes on the SH-60 
Helicopters. 

# All 38 CORROSION 
RESISTANT COATINGS 
FOR MAGNESIUM 
TRANSMISSION 
GEARBOXES FOR SH60. 

Magnesium alloys are widely used on 
aircraft components due to its light 
weight and manufacturability. One 
example of its use is the transmission 
gearbox on an SH-60 Helicopter 
as shown Figure 3. Although 
magnesium and its alloys have many 
attractive properties, they also have 
very poor corrosion resistance. In 
the case of the gearbox, significant 
corrosion occurs around the bolt 
holes and recessed areas requiring 
removal and repair or replacement 
of the gearbox as shown in Figure 
4. Conventional corrosion reduction 
methods employed on the gearbox 
involve hazardous coating processes 
and have limited effectiveness. 

The primary objective 
of this project is to implement a 
coating system that can be applied 
to the ZE-41 magnesium alloy in the 
SH-60 transmission housing. An 
effective coating system will provide 
a corrosion resistant layer that will 
greatly extend the service life of the 
housings and will also allow for the 
repair of housings that are removed 
from service due to extensive 
corrosion. The coating technique will 
also be extended to the flight control 
bridge where both corrosion and 


4 2007 No. I iMAST Quarterly 













fretting wear are a problem. 

The selected coating 
process must not adversely affect the 
base material. Magnesium alloys, 
such as ZE 41, are very susceptible 
to damage from excess heat and 
magnesium alloys readily react 
with molten material deposited 
by conventional thermal spray 
methods. It has been demonstrated 
that HVPC can apply corrosion and 
wear resistant coatings to steel and 
aluminum substrates with minimal 
effect on the substrate and presumably 
could be effectively utilized on 
magnesium alloy substrates. It 
is anticipated that the successful 
application of an HVPC coating to 
critical gearbox areas will achieve 
multiple goals: 

• Repair and recovery of damaged 
transmission housings 

• Extended life for transmission 
housings 

• Improved readiness 

• Reduction of use of hazardous 
coating processes 

• Decreased work load by reducing 
mean time between repairs 

The goals specific to this 
project involve the use of HVPC to 
produce a corrosion resistant coating 
on a magnesium alloy substrate 
(ZE41). The coating will be optimized 
for corrosion resistance and adhesion 
to the substrate with the requirement 
that the coating must not adversely 
affect the mechanical properties of 
the substrate. Additional work will 
include application of a coating to 
non-uniform substrate with recesses 
and dents to simulate repair of a 
severely pitted surface. 

Candidate coating 
materials have been identified 
and include commercially pure 
aluminum, 4047 A1 containing 12% 

Si for wear resistance, and 5356 A1 
containing 5% Mg which has good 
compatibility with magnesium alloys. 
In similar work, aluminum coatings 
have been successfully applied to 
aluminum substrates with good 
adhesion characteristics. Micrographs 



Figure 5. Micrograph of 7090 Al on aluminum 
7075-T6 substrate, lOOOX 

of the coating/substrate interface 
are consistent with a well adherent 
coating and show no significant 
porosity as shown in Figure 5. 

The coatings have demonstrated 
acceptable adhesion with bond 
strengths exceeding 48MPa (7000 psi). 

In the present project, 
initial screening of the coatings 
is underway utilizing a fractional 
factorial Design of Experiments 
(DOE) matrix to rapidly evaluate 
multiple process variables including 
pressure, temperature, stand¬ 
off distance, nozzle travel rate, 
powder feed rate, powder size, and 
substrate preparation method. The 
resulting coatings will be evaluated 
for corrosion resistance and bond 
strength. The most critical process 
variables identified in the screening 
will then be used to optimize the 
coatings characteristic. Evaluation of 
the optimized coatings will include 
tensile, fatigue, bend, bond strength, 
and corrosion testing. 

After the identification 
and confirmation of optimum coating 
processing conditions, technology 
transition of the HVPC process 
will occur with the installation of a 
coating system at NADEP - Cherry 
Point. The transition will include a 
demonstration on an SH-60 gearbox 
and training of appropriate personnel. 
Implementation of the HVPC process 
will involve multiple aircraft 
programs including H-60, H-53, H-46. 

The ManTech program 
is leveraged with an Environmental 



Figure 6. The results of energy dispersive x-ray 
spectroscopy, which verify the presence of MoS2 in 
the coating[l2]. 


Security Technology Certification 
Program Supersonic (ESTCP) titled 
Particle Deposition Technology 
for Repair of Magnesium Aircraft 
Components. Through the Navy 
Mantech and the ESPCP programs, 
a Joint Test Protocol has been 
established with the OEMs and 
representatives from the Navy and 
Army. Funding will be provided 
through the ESTCP program to 
install and qualify a HVPC system at 
NADEP-CP. 

NEW DEVELOPMENTS 

Self-Lubricating Coatings 

The Materials Processing Division 
has been working with researchers in 
Engineering Science and Mechanics 
Department at The Pennsylvania State 
University and at Wright Patterson Air 
Force Base to develop self lubricating 
coatings for high temperature 
applications. These coatings are being 
developed to reduce fretting wear 
between titanium alloy components 
in jet aircraft engines. The composite 
coatings had nickel as the matrix and 
either Molybdenum-disufide (MoS2) 
or Boron Nitride (BN) as the solid 
lubricant[12]. Process parameters 
were established for depositing the 
selected wear resistant coatings. 

The coatings were characterized 
for microstructure, bond strength, 
wear and distribution of lubricant. 

A typical microstructure showing a 
solid lubricant particle in the nickel 
matrix is shown in Figure 6. The Ni- 
BN composite coatings possess better 


iMAST Quarterly 2007 No. I 


5 










Figure 7. Average Vicker’s Hardness Number (VHN0.300) for uncoated and coated nickel, agglomerated 
and sinterediTAFA l375(Cr3C2-NiCr)),and blended (Cr3C2-Ni: PSU blend #2, PSU blend #9,PSU blend 
#2, andTAFA 1375V) coatings applied by HVPC process. 






Figure 9. Optical micrograph of laser glazed 
surface of PSU blend # 2: Cr3C2-25wt.%Ni, 
showing little porosity due to the increased density 
of the HVPC coating and dissolution with the 
substrate due to the increased energy. 

comparable hardness and adhesive 
strength relative to pure Ni coatings. 
Results indicated a reduction of 
friction coefficients with the addition 
of solid lubricants. Efforts to develop 
coatings that have higher amounts of 
lubricants are ongoing. 

Wear Resistant Coatings 
recent efforts have focused on 
developing process parameters 
required to apply Cr3C2-25wt.%NiCr 
and Cr3C2-25wt.%Ni coatings on 
4140 steel alloy for wear-resistant 
applications[13]. Improvements were 


made in the coating properties and 
microstructure through changes in 
nozzle design, powder characteristics, 
stand-off distance, powder feed rate, 
and traverse speed which resulted in 
an improved average Vickers hardness 
number comparable to some thermal 
spray processes as shown in Figure 7. 

Process optimization 
of the Cr3C2-based coatings 
resulted in increased hardness and 
improved wear characteristics. The 
improvement in hardness is directly 
associated with higher particle 
velocities and increased densities of 
the Cr3C2-based coatings deposited 
on 4140 steel alloy at ambient 
temperature. Selective coatings were 
evaluated using x-ray diffraction for 
phase analysis, optical microscopy 
(OM) and scanning electron 
microscopy (SEM) for microstructural 
evaluation, and ball-on-disc tribology 
experiments for friction coefficient 
and wear determination. A typical 
microstructure is shown in Figure 
8. The results show that HVPC is a 
versatile coating technique capable 
of tailoring the hardness of Cr3C2- 
based wear-resistant coatings on 
temperature sensitive substrates. 

Development efforts have 
extended to using post processing 
techniques to modify the coating 
properties. Laser glazing was 


investigated as a way of increasing the 
coating hardness and bond strength. 
The microstructure of the modified 
HVPC coating is shown in Figure 9. 

Laser glazing can increase 
the hardness of coatings applied 
using the HVPC process. The depth 
of penetration can be controlled by 
adjusting the laser power and glazing 
speed. Microwave sintering is also 
being investigated as a method to 
modify the HVPC coatings[14]. 

Effects of HVPC Coatings 
Mechanical Properties 

Work is on-going to better understand 
how the application of coatings 
using the HVPC process affects the 
mechanical properties of the substrate 
materials. In this study, two different 
cold spary processes were used to 
apply a thin layer of Commercially 
Pure (CP) A1 on thin plates of A17075- 
T6[15]. Nitrogen and helium were 
useds as the carrier gas to deposit the 
CP A1 powders. Characterization of 
the coatings included microstructural 
analysis, hardness measurements, and 
tensile, S-N fatigue and bend tests. 

The tensile and fatigue properties of 
the substrates were measured in the 
as-sprayed conditions and after heat 
treating to an overaged condition. 
Although there were not enough 
samples to produce statistically valid 
results, trends indicated that there is 
a relationship between mechanical 
properties of the coated substrate and 
the depostion velocity of the powders. 
Additional testing is underway to 
better understand this relationship. 

Other Materials 

Research continues on the deposition 
of composite materials that have 
very high thermal conductivity for 
thermal management and direct 
write applications. Direct write 
applications include circuits and 
patch antennas. Development efforts 
are being extended to nonmetahic 
powders. 


6 2007 No. I iMAST Quarterly 

































































REFERENCES 

1. A.R Alknimov, et.al.,”A Method of Cold 
Gas Dynamic Deposition”, Dokl, Acad. 
Nauk SSSR, 813, pp. 1062-1065, 1990. 

2. A.P. Alknimov, et.al.,”Cold Gas Dynamic 
Deposition Method for Applying a 
Coating”, US Patent 5,302,421, April 12, 
1994. 

3. http://www.gordonengland.co.uk/ 
coldspray.htm 

4. T. Stoltenhoff, H. Kreye, H. J. Richter, 

An Analysis of the Cold Spray Process 
and its Coatings, Journal of Thermal 
Spray Technology, 11 (4), 2002, pp.542- 
50. 

5. V. F. Kosarev, S. V. Klinkov, A. P. 

Alkhimov, A. N. Papyrin, On some 
aspects of gas dynamics of the cold spray 
process. Journal of Thermal Spray 
Technology, 12 (2), 2003, pp.265-81. 

6. D. L. Gilmore, R. C. Dykhuizen, R. A. 

Neiser, T. J. Roemer, M. F. Smith, Particle 
velocity and deposition efficiency in the 

CONTINUED FROM COVER 


from the approved Navy vendor for 
comparison evaluation. Following 
development of test hardware and 
evaluation techniques, new and 
repaired gears were tested under 
loaded conditions to failure. Strength 
and durability characteristics were 
evaluated on both the new and repaired 
gears. This evaluation included Single 
Tooth Bending Fatigue (STF), Contact 
Fatigue (CF), and Scoring Resistance 
(SR) tests on resident ARL Penn State 
equipment. Results of ARL Penn State's 

INSTITUTE NOTES 



cold spray process. Journal of Thermal 
Spray Technology, 8 (4), 1999, pp.576-82. 

7. Personal Communication, Army Research 
Laboratory 

8. M. Grujicic, C. Tong, W. S. DeRosset, D. 
Helfritch, Flow analysis and nozzle-shape 
optimization for the cold-gas dynamic- 
spray process. Proceedings of the 
Institution of Mechanical Engineers, Part 
B:Journal of Engineering Manufacture, 

217 (11), 2003, pp.1603-13. 

9. D. L. Gilmore, R. C. Dykhuizen, R. A. 
Neiser, T. J. Roemer, M. F. Smith, Particle 
velocity and deposition efficiency in the 
cold spray process. Journal of Thermal 
Spray Technology, 8 (4), 1999, pp.576-82. 

10. T. J. Eden, J. D. Hoggard, and J.K. Potter, 
“HVPC Cost Estimator”, PSU Invention 
Disclosure Number 2003-S078, July 24, 
2003 

11. T.J. Eden, and Potter, J.K.”AVV Enhanced 
Applique Armor Kit Product 
Improvement,”, Navy ManTech Final 
Report, Oct, 2005 


12. P. Walia, “Development of Ni-Based 
Self-Lubricating Composite Coatings 
for Ti-6A1-4V Dovetail Joints using the 
Cold Spray Process”, Masters Thesis, The 
Pennsylvania State University, University 
Park, PA, Aug 2007 

13. Wolfe,D.E, et.al. “Investigation and 
Characterization of Cr3C2-based Wear- 
Resistant Coatings Applied by the Cold 
Spray Process”, Journal of Thermal Spray, 
Sep 2006, Vol 15 

14. B. W. Shoffner, “Investigation of 
Microwave Sintering on High 

Velocity Particle Consolidation Coatings”, 
Undergraduate Honors Thesis, The 
Pennsylvania State University, University 
Park, PA, May 2006 

15. J.E. Barnes, et.al., “Mechanical and 
Microstructural Effects of Cold Spray 
Aluminum on Al 7075 using Kinetic 
Metallization and Cold Spray Processes”, 
submitted to the Journal of Thermal 
Spray Technology 


Drivetrain Technology Center evaluation 
demonstrated that the repaired gears 
performed as well as new gears. In 
many instances the performance of 
the repaired gears was slightly better. 
This phenomenon is attributed to 
the improved surface finish, which is 
an additional by-product of the ISF 
process. 

Project results clearly 
demonstrate that the repair and reuse 
of surface damaged gears is a viable 
option for the Navy. Application of this 


process has the potential to provide 
a significant cost avoidance. This 
gear repair procedure has application 
towards all fixed-wing and vertical lift 
aircraft within the military, resulting in 
further across-the-board operations and 
service (O&S) savings. Implementation 
of this repair procedure is being focused 
at FRC East Cherry Point, with support 
from NAVAIR and The Boeing Company 
(manufacturer of the CH-46). For more 
information on this program effort, 
contact Suren Rao, Ph.D. at (814) 865- 
3537 or by e-mail at <sbrl@psu.edu>. 


DMC 2006 Concludes 

Members of iMAST recently participated in the annual Defense Manufacturing 
Conference, held in Nashville, Tennessee. Once again, leaders from government, 
industry, and academia assembled to exchange perspectives and information 
relative to manufacturing technology, industrial modernization, and related DoD 
transformational initiatives. This year’s theme “ Superiority...Affordability...Can 
We Really Have Both?” set the stage for forum discussions concerning the defense 
industrial base and its impact on U.S. warfighters, who are currently engaged in 
full-scale combat in Southwest Asia. The conference featured senior guest speakers 
from the Department of Defense and industry, as well as various flag officers from 
the military services. Next year’s annual conference will be held in Las Vegas, 
Nevada from 3-6 December. 


iMAST Quarterly 2007 No. I 


7 















CALENDAR OF EVENTS 


2007 

9-1 1 Jan. 

Surface Navy Association Symposium 

★★★★★★★ visit the iMAST booth 

Crystal City, VA 

30-31 Jan. 

ShipTech 2007 

★★★★★★★ visit the iMAST booth 

Biloxi, MS 

3-5 April 

Navy League Sea-Air-Space Expo 

★★★★★★★ visit the iMAST booth 

Washington, D.C. 

6-19 April 

Aging Aircraft Conference 


Palm Springs, CA 

10-12 April 

SME Composites Manufacturing 


Salt Lake City, UT 

1-3 May 

American Helicopter Society Eorum 63 

★★★★★★★ visit the iMAST booth 

Virginia Beach, VA 

7-9 May 

Navy (SBIR) Opportunity Eorum 


Crystal City, VA 

30-31 May 

Letterkenny Depot Business Showcase 

★★★★★★★ visit the iMAST booth 

Chambersburg, PA 

31 May - 1 June 

Johnstown Showcase for Commerce 

★★★★★★★ visit the iMAST booth 

Johnstown, PA 

30 July - 2 Aug 

ONR Naval Industry Partnership Conference 

★★★★★★★ visit the iMAST booth 

Washington, D.C. 

20-24 Aug 

Penn State Rotary Wing Technology Short Course 


University Park, PA 

TBAAug 

Armstrong County Showcase for Commerce 

★★★★★★★ visit the iMAST booth 

Kittanning, PA 

TBA Oct 

Expeditionary Warfare Conference 


Panama City, EL 

2-4 Oct 

Marine Corps League Modern Day Marine Expo 

★★★★★★★ visit the iMAST booth 

Quantico, VA 

29 Oct - 1 Nov 

U.S. Coast Guard Innovation Conference 


New Orleans, LA 

13-16 Nov 

DoD Maintenance Conference 


Orlando, EL 

3-6 Dec 

Defense Manufacturing Conference 

★★★★★★★ visit the iMAST booth 

Las Vegas, NV 


Quotable 


“We are short of money.Therefore, we must start to think.” 

— British Physicist Lord Rutherford 


penn State 

^ 3 ^ 



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State College, PA 16804-0030 


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8 2007 No. I iMAST Quarterly