RPC-Overview

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Pitting and Crevice Corrosion Tests
In studies of exposure to 6% w/w ferric
chloride, Silcosteel®-CR treated 316L
stainless steel outperformed untreated
316L steel by a factor of 10. This test was
conducted per ASTM G48, Method B.
1000 Hour Salt
Spray Tests
Silcosteel®-CR treated
316L steel showed no
sign of attack after
1000 hours of salt
spray exposure ,
per ASTM B117.
Condensing
Humidity Tests
Silcosteel®-CR treated
316L steel withstands
environments
simulating outdoor
exposure, per
ASTM D 4585.
Cyclic Polarization Electrochemical Tests
Electrochemical corrosion testing of Silcosteel®-CR
treated 316L stainless steel yielded the following
corrosion and pitting potentials in neutral and acidic
conditions, per ASTM G61.
Breakdown or pitting potential, Eb , in millivolts.
Neutral Solution Silcosteel®-CR Bare Steel
100ppm chloride >3000 674
3000ppm chloride 1460 370
5000ppm chloride 1590 285
Acidic Solution (1N H2 SO4)
100ppm chloride 1128 580
3000ppm chloride 927 370
5000ppm chloride 983 563
Corrosion of Silcosteel®-CR treated 316L stainless steel versus
bare stainless steel at 3000ppm Cl - concentration.
Neutral Solution Silcosteel®-CR Bare Steel Improvement
Corrosion Rate, mpy 0.0009 0.04 50X
Breakdown Potential, Eb 1460 370
Acidic Solution (1N H2 SO4)
Corrosion Rate, mpy 0.05 0.83 10X
Breakdown Potential, Eb 927 370
Restek Performance Coatings • 800-356-1688 • 814-353-1300 • 27
untreated Silcosteel®-CR treated
untreated Silcosteel®-CR treated Silcosteel®-CR treated untreated