I just googled to see if other people had similar problems like yours, W10 TF2 graphical glitches and found this reddit post
https://www.reddit.com/r/tf2/comments/3j3alg/black_graphical_glitch_since_upgrading_to_windows/
Someone said switching to dx8 fixed it for them, but no one else said whether or not they tried dx8 on w10 so I don't know how viable that is. Shouldn't take too long to at least try though. GL