Tooth Root Optimization of Powder Metal Gears
Powder metal gear manufacturing allows for a root design that may be optimized with respect to stress. Conventional gear cutting using a hob is a balance between tool wear, kinematics, hob tip geometry and achieved tooth root radius. With PM manufacturing technology a root design that reduces stresses from bending, compared to a machined root design, can be built into the compaction tool. This paper will give some examples between stress levels from conventional root design using a Hob and stress levels using an optimized root design possible with PM manufacturing. The paper will also investigate how PM can reduce stresses in the root from transient loads generated by abusive driving.