corrosion


Advanced composites do not suffer from any form of corrosion and so there is no requirement for cleaning or flushing with fresh water. Even in a harsh marine environment there is no need to consider the problems of galvanic corrosion with tools, equipment, electrical wire and cabling or contact with other vessels.

Advanced composites do not suffer under any environmental conditions. They can accommodate high temperature environments and are immune to degradation due to high levels of ultraviolet light and extreme exposure to direct sunlight as found under tropical conditions.

 

Advanced composites are also best in low temperature environments such as arctic and sub-arctic conditions.

Even marine grade aluminium is subject to corrosion. In a marine environment careful monitoring of aluminium is required for early signs of corrosion. In order to keep structural weight to a minimum, hovercraft typically use thin sheets and so it does not take long for corrosion to have a debilitating effect on the structure. Typical causes of aluminium corrosion are:

  • When moored alongside steel-vessels the mooring connection can cause galvanic corrosion (two dissimilar metals touching) that will cause the hovercraft to act as a sacrificial anode.
  • Any steel tools and wires inadver- tently left in the bilges will cause galvanic corrosion rapidly attacking the aluminium structure. This is also a problem with any dissimilar metal within metallic equipment fitted to an aluminium vessel.
  • Lying water or moisture left in a close, inaccessible chambers will cause corrosion that only becomes obvious after the structure has degredated from the inside.

 

Corrosion of LCAC


Excerpt from SLEP (service-life extension program) for the aluminium LCAC30:

 

"Phase II. Buoyancy box (aluminium hull) replacement will be conducted at the Textron Marine and Land Systems facility in New Orleans, LA, where Textron will use design changes, coatings, and changes in materials to increase the LCACs resistance to corrosion. ...."

   

  copyright ABS 2014