The polycrystalline disk is fabricated with {HEAD ~ protruding portions} in {TAIL ~ the location} where the blades are to be bonded 
in
The polycrystalline disk is fabricated with { HEAD ~ protruding portions } in { TAIL ~ the location } where the blades are to be bonded
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH