Transcript Corrosion Data Update

Using Chemical Vapor Deposition
Processes to Enhance the
Corrosion Performance of Steel
Substrates
SilcoTek Corporation
Gary Barone
Topics
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About Us
Products and Applications
Product Performance
Conclusion/Future Product Development
APPLICATION AREAS
• SilcoNert™: Inertness
• Silcolloy™:Anti-Corrosion
• SilcoKlean™: Anti-Coking
• SilcoGuard™: Ultra-High
MARKET AREAS
Analytical
Pharmaceutical
Environmental
Petrochemical
Chemical
Process
Semiconductor/Research
Vacuum
Automotive
Basic Manufacturing Process
• Receive items
• Document – digital, customer contact
• Clean
– Standard: caustic ultrasonic bath, 2 systems
– Custom: solvation via other means
• Chemical Vapor Deposition (CVD) Process
– Vacuum
– 400ºC
– silicon-based deposition
• Clean
• Document – digital, customer contact
• Pack, ship
Product Characterization
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Amorphous silicon CVD coating
Density: 2.33 g/cm3
Melting point: 1410oC
Max operating temp.
• 600oC to 1000oC: Silcolloy; SilcoNert 1000;
SilcoGuard
• 450oC SilcoNert 2000
• 1200A to 5um thickness, minimal
smoothing of surface
Coating Cross Section
316 SS
Auger Depth Profile
Coating Capabilities: Substrates
• Tubing:
– 0.004” to 0.5” ID
– 2000+ ft. continuous lengths
• Complex geometry parts (inside and out)
– Fittings, valves, frits
– Block manifolds, sample vessels
– custom parts
Sizes of reaction chambers
• “Standard” vessels:
– 12” diameter cylinder w/ 56” height
– 6” diameter cylinder w/ 72” height
– 10” diameter cylinder w/ 18” height
– 21” diameter cylinder w/ 42” height
• Large processing oven:
– 27” diameter x 26” deep
• Walk-in Oven:
– 4 feet by 4 feet by 5 feet
– 6 feet by 4 feet by 5 feet
Substrates Which Coat Well
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300 and 400 grade stainless steel
High carbon steel
Titanium
Ceramics
Borosilicate glass
Inconel®
Hastelloy®
Substrates with Issues
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Nickel / Nickel plating
Aluminum*
Monel®
Copper
Brass
Gold and Silver plated components
Chrome Plated components
Magnesium
Elastomers
*heat-dependent
Corrosion Resistance
of Coatings
Silcolloy™
Corrosion Resistance:
• Stainless steel surfaces susceptible to
attack from in chlorinated environments
and acidic exhaust environments.
• Corrosion resistant deposition is
insoluble in hydrochloric acid and
unaffected in salt water environments.
Corrosion Resist studies
• External Evaluation
– Certified corrosion
engineers (Matco)
– Spectroscopic
analysis
– Mechanical testing
– Electrochemical
Cyclic Polarization in neutral, acidic, alkaline
– Atmospheric corrosion
• ASTM moisture condensation
• Salt spray ASTM B117
– Stress corrosion cracking (MgCl2; ASTM G36)
ASTM G48 B Data: Pitting and
Crevice Corrosion
• ASTM G48 method B; Pitting and Crevice
Corrosion
– 6% Ferric Chloride solution
– 72hrs, 20ºC
– 316L Stainless samples w/Gasket wrap
Sample
Initial
Weight (g)
Final
Weight (g)
Weight Weight Loss
Loss (g)
(g/m2)
Silcolloy™ Sample 17
10.4105
10.3710
0.0395
19
Silcolloy™ Sample 28
10.1256
10.0743
0.0513
25
Silcolloy™ Sample 47
10.1263
10.0742
0.0521
25
Bare Sample 27
10.0444
9.5655
0.4789
231
Bare Sample 34
10.1265
9.6923
0.4342
209
Bare Sample 37
10.1007
9.6276
0.4731
228
ASTM G48 B (cont.)
• Bare 316L Stainless Steel coupon
showing severe crevice corrosion
ASTM G48 B (cont.)
• Corrosion resistant treated sample
showing no crevice corrosion and slight
pitting corrosion
ASTM G61 Data: Cyclic Polarization
• ASTM G-61; Cyclic Polarization Electrochemical
Corrosion Testing
– Acid, neutral, basic aqueous solutions with varying Cl- ion
concentrations (100, 3000, 5000ppm)
– EG&G VersaStat System, 23ºC
– 316L vs. Silcolloy™ on 316L & 304L
-CR vs 316L Raw:
50x improvement
Neutral solution;
3000ppm Cl-
Ec = corrosion potential
Ic = current density at Ec
Eb = pitting potential
CR = corrosion rate
Sample
Ec, mV
Ic, uA/cm^2
Eb, mV
CR, mpy
316 L
-418
0.096
370
0.04
Silcolloy™ 316 L
-533
0.002
1460
0.0009
304 L
-435
0.145
361
0.06
ASTM B117 Data: Salt Spray
• ASTM B 117 – “Practice for Operating
Salt Spray (Fog) Apparatus.”
– 4000 hour exposure
– 100 degree Fahrenheit
– 3.5% by weight sodium chloride
• Reproduces exposure to marine
environments.
ASTM B117 Data (cont.)
• Silcolloy™ treated samples showed no
signs of bleeding, rusting, or pitting
corrosion
ASTM B117 Data (cont.)
• The non-treated samples showed some
light surface rusting, but no signs of pitting
corrosion.
ASTM D4585 Data: Condensing
Humidity
• ASTM D 4585, “Practice for Testing the
Water Resistance of Coatings Using
Controlled Condensation.”
– 1000 hour study
– 100 degrees Fahrenheit
– Distilled water
• Reproduces exposure to atmospheric
conditions
ASTM D4585 (cont.)
• Silcolloy™ treated samples showed no
signs of bleeding, rusting, or pitting
corrosion
Silcolloy™ Advantages
• Longer Life:
– Extend lifetimes of equipment exposed to
corrosive environments and/or process streams
• Protection:
– Protection of high value equipment in corrosive
environments
• Inert:
– Provide enhanced corrosion resistance to
analytical equipment while maintaining inert
sample pathway
• High Temperature:
– High temperature stability up to 1000c
Silcolloy™ Applications
• Manufacturing/Chemical
– Process streams containing HCl
• Environmental
– Continuous Emissions Monitoring exposed to
stack gases from coal fired plants and incinerators
• Automotive
– Equipment used in Automotive Exhaust testing
and catalytic converter studies
– Diesel EGR & Turbo systems
• Marine
– Some preliminary evaluation of coating in marine
environments (offshore platforms)
Conclusions/Future
• Continual process improvement and new product
development for coatings:
– Improving the hardness of coatings
– Improved corrosion resistant coatings
– Hydrophobic surfaces for moisture sensitive
applications
– Protection of high nickel alloys such as Hastelloy®
and Inconel®
– Hydrogen embrittlement resistance.
QUESTIONS ?