If Diskpart wont fix them they prob really are bricked but try these steps
ive never had Hive brick a disk i couldn't unlock using this method
Step 1: run CMD as admin
Step 2: enter diskpart, type: diskpart
Step 3: (assumes you got into diskpart) type: list disk
Step 4: select the "bricked" drive, type: select disk + the disk number (1,2,3,w.e) i.e "select disk 2"
Step 5: (assumes you now have your "bricked" drive selected) type: clean
Step 6: type: create partition primary
step 7: type: format fs=ntfs (or w.e format you want the drive) . this will take a bit, have a coffee.
Step 8: type: assign (this assigns a drive letter and mount point)
step 9: exit diskpart, type: exit
the drive should now be 100% usable again!