Carbon fiber raw strength vs laminates

[violt]

If raw carbon fiber has strength of say 4000 mpa, how come it is reduced when put in epoxy laminate to become only 950 mpa?

 

[Summ]

Maybe because unreiforced cured epoxy resin is not as strong as the carbon fiber, usually it has flexural or compressive strength 125- 140MPa (commercially avail.) When the epoxy is reinforced with less than 4% of carbon fibers the strength of the composite will be increased in comparison to the epoxy but will not be able to reach the carbon fiber's strength.
Hope this helps.