TRI-SERVICE GREEN GUN BARREL
description
Transcript of TRI-SERVICE GREEN GUN BARREL
TRI-SERVICE GREEN GUN BARREL An Environmentally Friendly Deposition Process to Replace Aqueous
Electrodeposition of Chrome
HARD CHROME ALTERNATIVES TEAMPROGRAM REVIEW MEETING
KENNEDY SPACE CENTER13-14 DECEMBER 2000
U.S. Army Research, Development and Engineering Center Benet Laboratory
Watervliet, NY 12189-4050John D. Vasilakis, DSN 974-5692
INTERACTIONS
ACADEMIA
• New Jersey Institute of Technology
• Rensselaer Polytechnic Institute
• SUNY - Albany
• SUNY - Stonybrook
• Stevens Institute of Technology
• INDUSTRY OTHERS
• GDAS/SACO ARDEC CCL
• UDLP ARL
• Boeing GGB Partners
Problem / Objective
• ProblemEnvironmentally unfriendly materials and processCarcinogenic chemicals (Cr VI)8% of barrel cost due to environmental compliance (target of opportunity)
Watervliet Arsenal (120-155mm)Rock Island Arsenal (25mm)General Dynamics (25mm,30mm)
ObjectiveReplace the current material and process with an environmentally friendly process for gun barrel bore protection
What is CMS ?CYLINDRICAL MAGNETRON SPUTTERING
(sputtering circa 1780) (magnetron sputtering circa 1935)
+
-+
-
I
I
GND
I
Ie- e-
I
300V
10V
Target(Cathode)
Subst
rate
(Gun T
ube)
Plasma(Ionized Inert Gas)
MagneticField Lines, B
II
PlasmaPowerSupply
TargetPowerSupply
COLLISION
e
Ar
Ar+
Ta
e-
Accomplishments/Deliverables
Coating Thickness Lands - 1.56 mils Groves - 1.5 mils
Initial Evaluation Beta Tantalum Well Adhered
Effect of Post-Heating of Coatingon Rifled Barrel Section
Groove test following the heating of the coated section. Some alpha-Ta is beginningto precipitate. Adhesion is excellent.
Groove test of specimen CMS-00317 afterapprox 1.5 mil of plating. Mainly beta-Tatexture. Knoop hardness 800-900. Much ‘decohesion’ and interfacial failure
Only for non-autofrettaged guns
GROOVE TEST ON MUZZLE END OF M242 SECTION
Photomicrograph of the
muzzle section of a fired
Bushmaster tube section.
Groove tests for adhesion
were conducted after the
firing.
SPUTTERED COATING ON GROOVE
Coating changes from alpha to betaTantalum alongthe side of thegroove.
UNAFFECTED COATING ON LAND
Alpha Tantalum
SPUTTERING TOWER
Sputtering tower isholding a 44” long45mm diameter tubesection in preparationfor plating a 45mm Casius gun tube forthe InternationalFTMA program
The same tower is willbe used to plate the 25mm Bushmaster and the GAU-12.
COATING ADHESION TESTING
Chrome Platingon Gun Steel
viaAqueous
Electrodeposition
Tantalumon Gun Steel
viaCylindricalMagnetronSputtering
Tantalumon Gun Steel
viaCylindricalMagnetronSputtering
EXCELLENT ADHESION POOR ADHESION IMPROVED ADHESION
SCHEMATIC OF CYLINDRICAL MAGNETRON SPUTTER
PROCESS
LEVERAGED PROGRAMS
• Characterization ProtocolSEM
Atomic Force Microscopy
Metallurgy
Coating Thickness
• Pulse Laser Heating
• Laser Interferometry and Bond Quality
ATOMIC FORCE MICROSCOPY
Investigating evolving morphology
Plating alpha tantalum
After 45 minutes After 120 minutes
PULSE LASER HEATING
HC chromium/steel interface after 20 laserpulses at 0.9 J/mm2 HC
Laser Pulse Heating Simulation of FiringDamage on Coated Gun Bore Surfaces
Laser SystemLaser Systemshowing generation and detection of surface waveshowing generation and detection of surface wave
Detection Laser
Generation Laser
Specular Reflection
Surface WaveSample
Decay ofAmplitude
Coating
Substrate
Low FrequencySurface Wave
High FrequencySurface Wave
Investigate dispersion curvesfor coatings that are welded (good bond) or smooth contact (poor bond).
SUMMARY
• Successful first firing test.
• Preparing new test using a conforming chamber.
• Preparing a test with a newly designed center conductor that uses permanent magnets.
• Conducting commissioning tests on 45mm Casius gun to be used in FTMA program.
• First firing tests for 45mm planned for May, 2001