Abstract: Due to the huge volume， complex structure and end effect of wind power gear， it is difficult to realize the uniform heating of tooth profile and tooth width， which affects the final strengthening quality. In this paper， the average temperature， the maximum temperature difference and the relative temperature fluctuation rate are taken as the evaluation indexes of the heating effect. The temperature fields along the tooth profile and the tooth width direction of wind power gear in the scanning induction heating process are studied， and the phase transformation and hardening of the gear are analyzed. It is found that the temperature uniformity increases gradually in the direction of tooth width from top to bottom within a certain range， which is due to the drastic change of tooth structure thickness. To gears strengthened by induction hardening in steady-state positions， the depth of hardened layer in the direction of tooth profile is almost the same as the depth of macroscopic phase change layer， and the transition region is relatively narrow. The heating effect and strengthening result of gear scanning induction heating are expounded， which provides the research foundation for the wide application of high-performance steel materials in the field of wind power.

Key words: gear; wind power; induction heating; temperature uniformity; hardened layer