I put together this Space Marine Chapter Name Generator
a little while ago to provide a few suggestions on potential names for new Primaris Chapters. A few others already existed but I didn't quite like getting suggestions like the "Flying Hippos" or "Happy Badgers" etc.
Think I'll be going with the Fire Devils
as my Primaris Chapter name, was half tempted to make them loyalist or at least a questionable offshoot from the Word Bearers. Seeing as I have a huge WB 30k force that could double as a 40k marine army, without having to rebuy/paint all my Forgeworld toys