Patent ID: 7854995

Claim:
A high density forged dual helical gear including a body and a plurality of gear teeth produced by a method comprising the steps of: placing a heated sintered powder metal preform in a split mold cavity of a spilt mold die having a top die and a bottom die, wherein said top die has a top mold cavity and said bottom die has a bottom mold cavity, wherein said top mold cavity is a first helical gear shaped cavity, and said bottom mold cavity is a second helical gear shaped cavity, wherein at least one of said top die or bottom die is a rotating die member; and axially impacting the heated sintered powder metal preform with an upper punch and a lower punch, wherein at least one of said upper punch or said lower punch have teeth which mate with said first helical gear shape or said second helical gear shape respectively, and wherein whichever punch has teeth which mate with a helical gear shape is a rotating punch, wherein said heated sintered powder metal preform is axially impacted with sufficient force to densify said preform into the high density forged dual helical gear, wherein the high density forged dual helical gear has a density of greater than 92% of theoretical density, and wherein the grain size of the gear teeth is at least one range higher on the ASTM E 112 grain size chart than the grain in the body of the gear.