Study on multi-degree-of-freedom near-net-shape forming method for aviation spur gears
MENG Yang
ZHUANG Wuhao
HAN Xinghui
Abstract：[Objective]To meet the high-quality and high-efficiency manufacturing requirements of spur gears for aviation equipment,conventional single-degree-of-freedom forming processes such as die forging and extrusion suffer from insufficient tooth profile filling and excessive forming load when fabricating aviation spur gears.A novel multi-degree-of-freedom forming concept for aviation spur gears was innovatively proposed.By applying continuous local multi-degree-of-freedom loading via rolling dies,the metal flow capacity was improved and forming load was reduced.Meanwhile,the grain structure of gears was refined,and continuously distributed metal flow lines along the tooth profile were generated,which further enhances gear strength and extends fatigue life,thus provides a new technical route for manufacturing aviation spur gears with high strength,high toughness and long service life.[Methods]Firstly,finite element simulation was adopted to investigate the influence law of blank shape on tooth profile filling performance and forming load,based on which an optimized blank design method was proposed.Secondly,the laws of tooth profile filling,distribution and evolution of equivalent strain,as well as the evolution of metal flow lines during forming were revealed.Finally,multi-degree-of-freedom near-net-shape forming process test for aviation spur gears was carried out according to finite element simulation results.Grain size and metal flow line inspections were conducted on test specimens to verify the validity of the above finite element model and simulation results.[Results]The results indicate that the frustum-shaped blank can effectively improve tooth profile filling and reduce forming load,and aviation spur gear specimens with fully filled tooth profiles are ultimately obtained.Moreover,the multi-degree-of-freedom forming method introduces severe plastic deformation in the tooth profile region,which not only significantly refines gear grains,but also produces continuous metal flow lines following the tooth contour.Accordingly,the multi-degree-of-freedom near-net-shape forming technology enables high-performance manufacturing of aviation spur gears.
Keywords：Aviation spur gearMulti-degree-of-freedom near-net-shape formingLaw of plastic formingHigh-perfor-mance manufacturingForming process design
Publication Date：2026-08-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：9( 71-79 )