Bulletin AKI

Výzkumné články

Corrosion Damage and Restoring of Metal Statues on the Pillar of the Holy Trinity in Olomouc

Děd J., Novák P., Houska I.
2001, 45 (EN), 5–10

Citace (ACS): Děd, J.; Novák, P.; Houska, I. Corrosion Damage and Restoring of Metal Statues on the Pillar of the Holy Trinity in Olomouc. Koroze a ochrana materiálů 2001, 45 (EN), 5–10.

Citace (ISO): Děd, J.; Novák, P.; Houska, I. Corrosion Damage and Restoring of Metal Statues on the Pillar of the Holy Trinity in Olomouc. Koroze a ochrana materiálů 2001, vol. 45, no. EN, p. 5–10.

Corrosion damage of the forged copper statues concerned mainly iron support structure, anchoring elements and surface gilding. Heavily corroded iron armature parts were replaced by stainless steel (AISI 304) or by copper. Original iron parts without heavy corrosion were painted. Copper skin sheets joints were filled by silicon sealant and drainage holes were made. After cleaning approximately 70% of the gilded surface of the statues have been preserved but gold coating is completely undercorroded. Visually important parts without gold coating (14% of the surface) were retouched by sheet gold and/or acrylate paint filled with gold powder. Further degradation of original gold layer cannot be substantially limited, due to continuing external atmospheric exposition. All parts of the statue skin may be disassembled, which allows regular maintenance of the inside of the statue. Applied corrosion protection measures are extending lifetime of statues for hundreds of years.

Výzkumné články

Corrosion inhibitors in conservation of iron archaeological artefacts

Šilhová A.
2001, 45 (EN), 11–14

Citace (ACS): Šilhová, A. Corrosion inhibitors in conservation of iron archaeological artefacts. Koroze a ochrana materiálů 2001, 45 (EN), 11–14.

Citace (ISO): Šilhová, A. Corrosion inhibitors in conservation of iron archaeological artefacts. Koroze a ochrana materiálů 2001, vol. 45, no. EN, p. 11–14.

The factors are discussed participating in the secondary corrosion of archaeological rust coated iron artefacts during their storage in museum collections. The effect of usual corrosion inhibitors for iron in neutral environments were examined in combination with a partial desalination of the artefacts in an alkaline solution. A distinct positive effect was found after application of sodium benzoate and of tannin. On the contrary the potassium chromate and sodium nitrite exhibited even an unfavourable effect. We ascribe that effect to their oxidizing character participating in retardation of the desalination process.

Výzkumné články

The Mechanism of Action and Optimal Concentration of the Zinc Powder Particles in Organic Coatings from the Anticorrosive Efficiency Point of View

Kalendová A.
2001, 45 (EN), 15–20

Citace (ACS): Kalendová, A. The Mechanism of Action and Optimal Concentration of the Zinc Powder Particles in Organic Coatings from the Anticorrosive Efficiency Point of View. Koroze a ochrana materiálů 2001, 45 (EN), 15–20.

Citace (ISO): Kalendová, A. The Mechanism of Action and Optimal Concentration of the Zinc Powder Particles in Organic Coatings from the Anticorrosive Efficiency Point of View. Koroze a ochrana materiálů 2001, vol. 45, no. EN, p. 15–20.

The present work is directed to the study of mechanisms of the action of zinc powder as an anticorrosive pigment in the coating compositions based on the binder composed of a two-component epoxy, a single-component polyurethane, and epoxy-ester resins. The study has resulted in a finding that the neutralization and barrier mechanisms of action contribute to the anticorrosion-effective protection more than the electrochemical mechanism.