Test manufacture of the canister insert I35

This report describes the insert-manufacturing test of a disposal canister for spent nu-clear fuel that was made by Metso Foundries Jyväskylä Oy, in June 2004 on contract for Posiva Oy.

The test manufacture was a part of the co-operation development programme of encap-sulation technology between SKB AB and Posiva Oy.

Insert casting was specified according to the current manufacturing specifications of SKB. The canister insert was of BWR-type with integral bottom. This was the second trial manufacture of this type of insert in Finland and, in total, the third test manufacture of insert by Metso Foundries Jyväskylä Oy.

The result fulfilled all the requirements but the material mechanical properties of the cast material. The measured ultimate strength and elongation at rupture were lower than specified in the upper part of the cast. The reason for this was revealed in the metallur-gical investigation of the cast material. The cast contained slag (dross). Avoiding the dross formation will be the most demanding challenge of the forthcoming development of the cast procedure.