Hybrid Composite based on natural fibre

General Composites Discussions Composites Talk
#1

Can somebody tell me what is the best experimental test to justified the material to use as main material for car body?

For your information, natural fibres are:

  1. Woven natural silk fabric
  2. Woven mengkuang plant fibre (mats)

Hybridization of this fibre with glass fibre and epoxy resin will undergo a test, in order to justified the best layer sequence ( using hand lay up and sandwich lamination)of the hybrid composites.

My supervisor suggest to do 3 point bending ( delamination, Mode 1 and mode 2). Is that the test will show the best properties behaviour of composites for car body making??

thank you…

#2

Nawza,

Depending on the application, you probably want to do more tests on the specimen than a 3 point bending test. A few that some to mind are impact tests, thermal expansion and water absorption. Think about what properties are desirable in a car body and design a way to test the different variables.

  • Josh
#3

As usual, cost is a motivator for natural fibers.

There are several companies I’ve chatted with that make woven natural fibers (jute and hemp) for use in structural/semi-structural applications. Haven’t tried them but it makes sense to try if they’re cheap enough and durable enough. If nothing else these fibers help reduce the carbon foot print. I do use a bio based epoxy resin, and it seems to work great. Has good mechanical properties and is partly from renewable.

I keep reading about companies making natural fibers but haven’t really seen them available yet. There is one company in particular that takes plant fibers and breaks them down with an enzyme then ‘spins’ a tow like spider does, from the liquid. Supposed to be near the strength of E glass but, I don’t think they’re in full scale production yet.

Though the tests may tell you about the mechanical properties, which I"m sure can be improved by hybridizing the layup. Add some kevlar/carbon/glass. At which point the natural fibers really aren’t doing much but taking up space and absorbing resin.

#4

A couple years back, the Society of Manufacturing Engineers fabricated a skateboard for their annual competition out of Flax Fibers. It used a core down the center to provide a little bit of stiffness. I’m not sure how much resin the flax soaked up, but it seemed to be a good structural alternative to the structural reinforcements typically used.

Here is a small description about the project. Scroll down to the bottom of this link and you can see a picture of some of the team members holding the boards they built.
(https://www.sme.org/MEMagazine/Article.aspx?id=65883&taxid=1416)

#5

You will need to do a normal tension (tensile) and compression testing as well. This will show you what the material is capable ot handling, and then you will need to see what layer combinations will be better.
I think a water absorption and even UV aging would be a good one too! Being natural fiber, it WILL suck up water!