Technischer Bericht NTB 84-04
Korrosion und Korrosionsschutz von Endlagerbehältern aus Eisenwerkstoffen unter besonderer Berücksichtigung des schweizerischen Endlagerkonzepts
The report considers the system: container material/bentonite/formation water and reviews the existing information on this system relevant to the assessment of the safety of final disposal. For unalloyed iron materials the physico-chemical and chemical conditions are not critical as regards uniform corrosion, stress corrosion cracking and hydrogen embrittlement. The corrosion rates from direct water corrosion, soil corrosion and possible local corrosion effects are expected to be low, they must, nevertheless, be ascertained by experimental investigations.
The report further presents proposals concerning material technology and container designs; examples are calculated. An additional weld overlay with nickel alloys and/or a ceramic coating can lead to an even higher resistance against corrosion. Welding technology and quality assurance are discussed in detail.
The study shows that it is possible to manufacture containers to safely dispose of high-level radioactive waste inside a bentonite backfill in crystalline formations.
