why can’t kevlar stop rifle bullets even though it’s strong than steel on an equal weight basis?

Question

Ar500 steel plate can stop rifle bullets. In my brain I’m thinking like “well if kevlar is stronger than steel, then slab of kevlar of the same size of an ar500 plate should stop rifle bullets too”. Clearly it doesn’t and I don’t understand why

In: Engineering

Answer 1

Its not only about stopping the bullet, but also about dispercing the force to a greater area. Kevlar might hold the rifle bullet, but its to flexy to disperce it around and damage will be significant. Steel plate is rigid and impact will be spreaded through all its surface. Even then its still a huge impact and very painfull.