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NO-BLAST SEM analysis

Passivity layer

  1. Rust layer: Upper layer of passive film caused by 2nd chemical reaction between NO-BLAST and substrate surface
  2. Interface layer: Layer caused by 1st chemical reaction between NO-BLAST and substrate surface

NO-BLAST analyzed by EDS

Photographing surface layer for analyzing it through EDS
(Magnification: 20kv x 300)

※ EDS (Analyzer of elements)

Element Weight% Atomic%
C 5.78 10.86
O 43.34 61.12
Na 0.58 0.57
Al 0.23 0.19
P 21.50 15.66
K 0.71 0.41
Fe 26.74 10.80
Zn 1.12 0.39
Total 100.00

Elements of the surface of corrosion layer

Spectrum through EDS PEAK

Analysis through XRD after applying NO-BLAST on corrosion layer

Fe₂+ +2H2O Fe(OH)₂+H₂(ferrous hydroxide)
→2Fe(OH)₂+½O₂+ HO → 2Fe(OH)₃(ferric hydroxide)
→2Fe(OH)₃+FeO₃+ 3H ₂O (stable structure)

Main substance of the rust of a sample is FeO(OH) according to the result of analysis through XRD.
After using the two types of corrosion inhibitor, the substances of the surface are as follows:

A type (Blue) : Fe3KH14(PO4)84H2O, KFe3H8(PO4)66H2O
B type (green) : Fe3KH14(PO4)84H2O, (Fe0.84Al0.16)3KH14(PO4)84H2O
Fe3(NH4)H14(PO4)84H2O

FeO(OH) layer is formed and the rust on the metal surface is completely removed..

NO-BLAST corrosion resistance Salt spray for 400 hours

Blasting+Primer Coating + Top Coating

Blasting + NO-BLAST+ Top Coating

Blasting + Rust Forming + NO-BLAST+Top Coating

  • Applying Primer Paint: Corrosion seriously occurs between steel and primer paint (over 6mm).
  • Applying NO-BLAST: Anticorrosion layer is created between NO-BLAST and steel to prevent corrosion and restrict corrosion occurrence.

NO-BLAST adhesive strength test

After using NO-BLAST to convert rust, minute crack is created. Adhesive sterength:5.7 Mpa
(based on ASTM D 4541)

Surface between converted area from corrosion and paint after test

minute crack

Comparison of adhesive strength test of organic coating

Test sample: Carbon steel (70 x 150 x 3t) Shot Blast + corrosion caused by outdoor exposure

Adhesive strength result of each sample type

Category
(Type of Sample)
How to Manufacture After Test Result
(MPa)
Remarks
NO-BLAST Blasting+Corrosion +WireBrush+ NO-BLAST+Top Coating 7.436
7.011
ASTM

D4541 D3359B

NORSOK M501기준
NO-BLAST Blasting+ Corrosion+NO-BLAST+ Top Coating 6.735
5.929
Sample of Other Company (A)
Blasting+ Corrosion+A+Top Coating 2.827
Unavailable to test
Sample of Other Company (B)
Blasting+ Corrosion+B+Top Coating 1.611
Unavailable to test