Kendra Little talks partition elimination:
Working with table partitioning can be puzzling. Table partitioning isn’t always a slam dunk for performance: heavy testing is needed. But even getting started with the testing can be a bit tricky!
Here’s a (relatively) simple example that walks you through setting up a partitioned table, running a query, and checking if it was able to get partition elimination.
I would have snipped the tl;dr section but it was too long…