Abstract: A method for producing a fully dense powder metal helical gear including placing powder metal in a preform die wherein it can be compacted axially by punches to create a gear preform having various gear profiles such as a helical profile, sintering the preform, and inserting the sintered preform into a hot forming die wherein it is impacted axially by punches to fully densify the gear preform. The densified gear can be inserted in a burnishing die where a more precise gear profile can be imparted resulting in more precise dimensions. Finishing treatments, such as rolling, shaving, heat treating, machining to length and inner diameter sizing can be subsequently performed.

Abstract: A method for producing a fully dense powdered metal helical gear can include the steps of placing powdered metal in a preform die wherein it can be compacted axially by rotating punches to create a helical gear preform. Next the preform can be sintered. The preform can then be heated to an appropriate temperature and inserted into a hot forming die wherein it can be impacted axially by a rotating punches to fully densify the helical gear preform. Next the densified helical gear can be inserted in a burnishing die where it can be forced through a helical profiled die cavity to impart more precise external dimensions. Process temperatures and impact forces can vary depending on the properties of the powdered metal and desired characteristics of the finished part. Secondary treatments, such as rolling, shaving, heat treating, chining to length and inner diameter sizing can be subsequently performed.