At this time it does not look like Samuel L. Jackson will appear as Nick Fury in the upcoming Avengers: Infinity War or Avengers 4, but you never know.
In addition, it appears that Nick Fury will not show in Avengers: Infinity War as well.
Paul Bettany’s Vision character will be back for Avengers 4 while Samuel L. Jackson’s Nick Fury will be sitting this one out.
On the other end of the spectrum, we’ll have to wait for the release of Captain Marvel in 2019 to see Samuel L. Jackson as Nick Fury as he will not be in Avengers: Infinity War, Black Panther, or Avengers 4.