a problem we are having with composites

Hey everyone we are working on composite materials as a part of our final year project. We designed and fabricated a carbon/epoxy composite plate and kept the same for curing 3 days ago. But the plate is still somewhat sticky giving us a feeling that the resin has not yet hardened. What could be the cause of this problem?

Please help us out.

Easy Math Editor

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Comments

What is the temperature you are keeping for curing... Usually it takes 72 hours if kept at 30° C

Pravin Luthada - 7 years, 1 month ago

We kept it at room temperature only which is around 40°C these days

Swapnil Harkanth - 7 years, 1 month ago

I have seen the smiler phenomena as mentioned in your problem when we kept the job in 20°c. Even after 72 he's it was in gel condition only Can you tell me what is the resin and hardner with respective amount .... Some time that can be the reason

Pravin Luthada - 7 years, 1 month ago

@Pravin Luthada – It is actually almost done now..we kept the plate in sunlight for the entire day and it kinda worked because of the scorching heat these days..the resin is epoxy and hardner we received from the supplier as a package with the resin so i dont know its grade but we used it in 1:2 hardner:resin ratio..

Swapnil Harkanth - 7 years, 1 month ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$