Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Use shift+alt+i on the selected rectangle in Inkscape to get the tile this is based on
Source Firkin
Inspired by a drawing seen in 'City of Liverpool', James Picton, 1883.
Source Firkin
I have no idea how to describe this one, but it’s light and delicate.
Source JBasoo
This was formed by distorting an image of a background on Pixabay.
Source Firkin
One more updated pattern. Not really carbon fiber, but it’s the most popular pattern, so I’ll give you an extra choice.
Source Atle Mo
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A simple but elegant classic. Every collection needs one of these.
Source Christopher Burton
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Sharp but soft triangles in light shades of gray.
Source Pixeden