Formation of micro-cracks at the surface of a high voltage cable screen induced by aluminum corrosion

The main purpose of this study is to investigate the
adhesion between corroded aluminium conductor strands
and the semi-conductive cable screen. In this paper it is
proposed that increased adhesion is one of the pre-requisites for the local degradation of the semi-conductive
cable screen causing severe water treeing in the XLPE
insulation. A model test set-up was developed and used
including samples with a dried corrosion layer between a
heat pressed semi-conductive cable screen and an
aluminium metallic surface. The results show that the
adhesion was strongly increased when the Al surface was
corroded.
KEYWORDS
HV subsea cables, water treeing, stress induced
electrochemical degradation, corrosion, adhesion.