Gears are common mechanical components used for power transmission, speed regulation, and motion control. Although gears may be cast, extruded, or roll formed for noncritical applications, gear tooth forms and other dimensions must be precisely machined in applications requiring high load capacity, long fatigue life, and minimal vibration. Many common mechanisms, such as automotive transmissions and stationary gearboxes, contain multiple machined gear sets, and high-precision gears are critical components in jet engine, helicopter transmission, wind turbine, and oilfield applications [1–5]. Most precision gears are machined from ferrous alloys or powder metals.