Impact testing on various materials

A friend of mine did this testing recently. Kind of a "let's see what happens adventure".

 

That material property is called "toughness". It is the amount of energy it can absorb before breaking.

 

I'd be curious to see production deck laminate.

approximate;
skin 450g csm
bulk 900g csm
bulk Press in wet ; 1/2" 6 lb PET foam (Airex T92.100 or Armacell GR100)
bulk 900g csm
bulk 24 oz WR, 2408 0/9o, or 3610 0/90

 

usually it is a ball or rounded end of a cylinder as it is more indicative of point load or local impact. With a sharp edge of a cylinder, that will cause shear.

 

Yes, in this he was talking about hitting rocks and using what he had.

 

The video showed he was testing and talking randomly. Airex has the lowest shear strength but the greatest tenacity. Meaning it just stretches and refuses to give up. That is why there is that "rubbery" feel. If you want a flexible boat, use Airex.

A more exhaustive and scientific test on sandwich laminate was made before and was published in PBB a long time ago. Attached is the inset of the article.

A complete study of impact testing on various laminates (includes CF) and cored composites and its effect was in the first edition of Marine Composites by Eric Green and associates. Unfortunately, only the second edition can be downloaded in the net. The impact test and formula was omitted. I have the hard copy of the first edition.

 

The toughness is the area under the curve for each material. That is the amount of energy it absorbs before breaking.