Degree of Cure
Degree of Cure
(OP)
Does any one have any information relating degree of cure to Elastic Modulus and Shear Modulus for PMCs. How is degree of cure calculated? Or is it observed? I have tensile tested coupons of S-2 Glass(90o) and Carbon-Carbon and was curious if this could have an effect on ultimate strength?
Thanks,
Hex
Thanks,
Hex





RE: Degree of Cure
(exotherm, delta H, in joules per gram) can be measured on a an already cured sample then it was not fully cured. The percentage of cure can be calculated by dividing the residual delta H by the total delta H.
Degree of cure can have a very strong effect on strength and modulus. Some materials can be over-cured as well as under-cured. Over-curing causes excessive crosslinking which makes the polymer more brittle.
Degree of cure is not relevant to carbon-carbon because the polymer has been pyrolyzed into carbon and isn't a polymer anymore.
RE: Degree of Cure
Compositepro,
Is incomplete pyrolyzation possible? If so would an additional heat treatment rectify the condition?
Thanks
RE: Degree of Cure
Fiber properties change with heat treatment as well as matrix properties. So carbon-carbon parts are often made with cheaper oxidized PAN fibers or standard modulus fibers which are much less fragile that the high modulus fibers.