Answer:
The carbon fiber itself will withstand incredibly high temps. The weak point will be the epoxies or the resins.Ambient-cured epoxies will typically begin breaking down around 100 °C. The heat-cured epoxies that will go up to around 300 °C. As you get into the high temp ratings, the epoxies get trickier to handle, install, cure.Since the compositions of most irons while casting are around the eutectic point (lowest liquid point) of the iron–carbon system, the melting temperatures usually range from 1,150 to 1,200 °C.As is evident, at such high temperatures, the epoxies of Carbon Fibers will melt. So, they are not yet used for iron casting.