English to Spanish Other Manufacturing lab tests

The context is a lab test category "Materials with a pile surface which produces a flash effect on the aproach of a flame". Pile Surface is a surface of short hairs or strands on a carpet, rug,ect. Kind of like Velvet. Very short hairs all cut to the same height. I have no idea what this is called in spanish. I would use "superficie aterciopelada" but it's not exact. I'm sure this must already have a translation into spanish, in the business. Let's see.