Composite hull vs Alloy hull ?

It seam we got a customer for our actual passagemaker alloy hull...

http://www.long-cours62.com/article-passagemaker-cherchez-l-erreur-77177400.html

Normally we will built an evolution of Hoa and a collègue project to built also a similar evolution for him.

Normally she will be the profile N°6

http://www.long-cours62.com/2015/02/un-compromis-oui-mais-lequel.html.

In the same time a boatyard contact us and propose to built this hulls in "composite" (sandwich epoxy, fiber glass, Kevlar, 50 mm foam 100 kg/m3 ).

One of the advantages (for me ) for alloy built is the resistance in case of ice friction (sorry for my English)


For example the weight of Hoa :
-deck is around 23kgs/m2 (including plating 6 mm, beam 80X12 and stiffeners 50x8 )
-around 36kgs/m2 for the hull above wl ( including plating 10 mm, frame 100x12 and stiffeners 60x8))
- around 42kgs/m2 for hull below wl. (including plating 12 mm, frame 120x12, stiffeners 60x8)
- around 56 kgs/m2 for the bottom ( includind plating 16 mm, stiffeners 60x8 but without the "floor" (varangue in French )

Your opinion on the pro/con alloy vs composite are welcome :?::idea:

 

The Pro's and Con's should be decided by the designer which is dictated by the SOR. Since one of the materials shall provided a "better" solution than the other - once designed (by that I mean one must complete the main 'design' for both and see which is best). And in that 'solution' is: ease of repair, availability of materials, cost, labour rates, weight saving (if any) etc etc... even before one looks at the actual physical properties.