mechanical properties of composite laminates

Discussion in 'Fiberglass and Composite Boat Building' started by Steve W, May 1, 2014.

  1. Steve W
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    Steve W Senior Member

    I am trying to find where testing has been done to find the mechanical properties of like cured laminates where the only variables are the resin used. I would like see the actual differences between epoxy, vinylester and epoxy laminates that are not supplied by a manufacturer of one particular type.

    Steve.
     
  2. TANSL
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    TANSL Senior Member

    Maybe I do not understand you well but to determine the mechanical properties of a laminate, the least important is the resin.
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    You rarely see epoxy laminates with a high resin to reinforcement ratio, or the other two with a low resin to reinforcement ratio, mainly because interlaminar bond would suffer, so I don't know that direct comparison is that easy.
     
  4. FishStretcher
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    FishStretcher Junior Member

    ASM interntaional has a handbook on composites- your local university library might have it. It is ~600 pages. There is a variety of resin and fiber comparison data in there. You have to know what you are looking for in terms of chemistry when you peruse it, as there are a lot of exotic resins listed too. Exotic for boats anyways, not for aerospace.

    When that fails, I have had a little luck searching the web by manufacturer- like Ashland chemical, or by name, like Derakane. If you know product names and brands, that might help. Assuming you don't want to buy a ~$300 tome for the answer, and you can't get it on inter-library loan.
     
  5. Steve W
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    Steve W Senior Member

    Thanks, I will look for that book, I have seen some results on specific laminates done as university papers but not directly comparing the same laminate with different resins. I would expect the result to be epoxy, VE and PE in order of tensile strength but how much is the difference? I may at some point when I have some spare time do some identical sample coupons and test them by hanging weights until they break, they would have to be small cross sectional areas in order for me to be able to break them though. My main interest is tensile and interlaminate shear.

    Steve
     
  6. FishStretcher
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    FishStretcher Junior Member

  7. rxcomposite
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    rxcomposite Senior Member

    Google "Composite Materials Handbook"- Department of Defense Handbook

    I have volume 2, Polymer Matrix Composite Materials Properties, 2002 version.

    It will take time to memorize all the symbols and abbreviations as it is based on micro mechanics. You also have to interpret the graph correctly as coupon test is carried out in varying temperatures. The graph shows the ultimate strength and the "knee" where the yield is.

    It is limited in such that it is mostly aerospace materials, high fiber content, aerospace eglass fabric weave and carbon fiber. You have to search other book for non noble materials such as ortho resins, iso resins, and CSM or thick "boat cloths" commonly used in the boating industry.
     
  8. Tad
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    Tad Boat Designer

  9. rxcomposite
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    rxcomposite Senior Member

    Marine Composites by E Green (Tad's link) has numerous data on laminates with polymer resin.
     
  10. mastcolin
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    mastcolin Senior Member


  11. Steve W
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    Steve W Senior Member

    Thanks guys, i will pick up a used copy of composites materials handbook online.

    Steve
     
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