Strongest Composite 1

[steveut]

I've spent a few weeks trying to find a very specific material and am running out of resources. I'm hoping someone may have an idea or be able to point me in the right direction.

I am looking for the strongest composite available based on these few criteria:

1) Discontinuous Matrix, moldable
2) Polymer filler
3) Strength > 50 ksi
4) Notched Impact > 10 ft-lb/in
5) -40 dC < Working Temp < 70 dC

So far I've discovered only one material that comes close. Quantum Composites QC-8800 has a TS of 50 ksi, 1" fibers, vinyl ester and an Izod notch of 35.

Thanks for any help.

Steve

 

[Compositepro]

Sounds like you found what you are looking for. What more do you want?

Chopped fiber molding compounds are what you are describing. The polymer is usually considered the matrix and the fiber is the reinforcement. There are sheet molding compounds and bulk molding compounds.

Bulk molding compounds can have 35% fiber and the consistency of bread dough. They can be extruded and transfer molded. They can also have 60% fiber and the consistency of dry chopped straw. This type can be much stronger and stiffer. Parts are made by compression molding where preweighed buckets of material are poured into hot molds and the press closes to compress and cure the material. Parts are removed from the molds hot.

Polyester resins are cheap but adequate for many applications like cicuit breaker casings. Epoxy and bismaleimide resins are much stronger and have higher service temperature (up to 600F for BMI). But they are more expensive and are used for aerospace applications.

The fibers can be glass or carbon.

 

[steveut]

Thank you for the reply. The material I found was handed to me by another engineer. I had not seen it despite weeks of looking. The material is good mechanically but I was looking for more options in case there are thermal, chemical or environmental concerns. I was hoping another material spec might be laying on someone else's desk. Thank you for the description, I will use that and go over my internet and literature search once more.

Does anyone have a site with sheet molding and bulk molding compounds mechanical properties listed?

 

[Albigger]

I haven't looked thru them all but YLA makes some bmc

http://www.ylainc.com/yla_products/...sion_molding&showcategory=0&cat1=Compression#

 

[steveut]

Thank you. Based on the above information I was able to find one more compound of similar mechanical properties.

http://www.complexcomposites.com

Their only material available I believe.

Steve

 

[PanelGuy]

I have a friend with whom I used to compound thermoplastic rsin and short fiber reinforcements with. Pretty much whatever you want. I do not know if he is still interested in doing it, but if you need a solutoin still I could hoook you up.