Complex sentence: The SiC-matrix of LSI has a very low porosity and protects the carbon fibers quite well, and brake disks do not heat up above 500 ° C for more than a few hours in their lifetime.
Split into simpler sentences: The SiC-matrix of LSI has a very low porosity, which protects the carbon fibers quite well. Brake disks do not experience temperatures above 500 ° C for more than a few hours in their lifetime.