NO-BLAST SEM analysis
Passivity layer
- Rust layer: Upper layer of passive film caused by 2nd chemical reaction between NO-BLAST and substrate surface
- 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 |
