forming a plurality of protrusions on the periphery of a polycrystalline superalloy disk, said {HEAD ~ protrusions} being shaped to conform to {TAIL ~ the blade} cavities 
shaped to conform to
forming a plurality of protrusions on the periphery of a polycrystalline superalloy disk , said { HEAD ~ protrusions } being shaped to conform to { TAIL ~ the blade } cavities
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH