ABSTRACT
The geometric parameters of test gears are as follows: normal module Mn = 5 mm, number of teeth z = 30, pressure angle αn = 20°, profile shift coefficient xn = 0, helix angle β = 0, six-grade accuracy. Manufacturing processes: forging-hardening and tempering-rough machining + fine machining + hobbing-carburizing (920°C) + high tempering (650°C) + quenching (830°C)— low tempering (180°C)—blast cleaning-grinding inside hole+grinding end face + grinding outer circle + grinding tooth. Finally, through accuracy measurements of test gears, all indications are within six-grade accuracy, fault-free by the ultrasonic flaw detection, and there aren’t grinding burns of root. The detection result of chemical elements is shown in Table 1, the test result of mechanical performances is shown in Table 2, the detection result of non metallic inclusions is shown in Table 3, the gradient distribution of hardness and picture of metallographic structure are shown in Figure 1 and Figure 2.
