Palmer sier at alt som trengs er å reingjøre skikkelig, så fikser oksygenet i lufta resten.
Min kilde, og den andre du lenker til anbefaler bruk av sitronsyre. Men det er ikke likegyldig hvordan du bruker den - og det sies klart i NASA-undersøkelsen. Jeg har bare lest den første delen av den, og det ser ut til å stemme med det som sies i den artikkelen jeg fant.
NASA-konklusjonen:
Optimization Phase 1 - Conclusions•In general, high temperature, low concentration, and longer processing time provide more corrosion resistance.–Temperature and processing time have larger effects than concentration. This finding agrees with testing performed by Boeing.–For 410, high concentration had a detrimental effect on corrosion resistance. For 304, concentration had almost no effect at all.•From the preliminary results citric acid is capable of providing acceptable results compared with nitric acid.The best citric acid treatment (180F 120min 4% citric acid)–Thebestcitricacidtreatment(180F, 120min, 4%citricacid)performed better than the typical nitric acid passivation treatment for flight hardware.HOWEVER several citric acid treatments especially those at room–HOWEVER, severalcitricacidtreatments, especiallythoseatroomtemperature, performed worse than no passivation treatment.
Jeg kan jo sitere den korte bruksanvisningen fra "min" artikkel:
- Clean the surface - The material must be free of all surface contamination before it can be passivated. Presence of any grease (e.g. from manufacturing), soil, fingerprints, etc. on the surface will prevent iron removal and oxide layer formation.[4][39][40][41][2][42] See Cleaning for quality methods.
- Add water - Fill a brewing vessel with water.
As a bonus you may also add any other stainless steel items that need to be passivated. Do not include items made from any metal other than stainless steel (such as carbon steel, aluminum, brass, or copper), because they will corrode.
- Apply heat - Heat the water to 140-180°F (60-82°C).
- Add acid - Stir in enough citric acid to make a solution of at least 4%. In other words, use anhydrous citric acid at a concentration of 40g/L, or 5.4 oz per US gallon.
- Allow to sit - Wait 2 hours or longer.
- Rinse - Drain the citric acid solution and rinse with clean water. Rinsing ensures the surface has full access to oxygen in the air, which creates the oxide layer.[43][1][4]
- Wait - The surface should be exposed to air for 8–24 hours before use. Passive film growth begins in seconds or minutes, however it takes several hours to stabilize.[44][2][42][45]
Kortversjonen av begge disse kildene:
4%-oppløsning av sitronsyre i to timer på 80 grader
Det var i grunnen det jeg lurte på om fagfolk synes virker bra.