难变形金属小模数齿形件电流辅助分形旋压成形方法研究

Research on splitting spinning method for small modulus toothed parts made of difficult-to-deformed metals by current-assisted forming

针对难变形金属小模数齿形件采用传统滚齿及插齿方法制备时,存在材料利用率低、强韧性不足等问题,提出采用分形旋压方法实现此类小模数齿形件的完整近净成形。以模数为0.3的30CrMnSiA合金结构钢小模数齿形件为研究对象,设计制作了难变形金属小模数齿形件分形旋压成形工艺装备,并基于旋压成形试验进给研究了渐进式进给、主轴正反转进给和间歇式进给3种不同成形方式及有/无电流辅助条件对难变形金属小模数齿形件分形旋压的影响规律。结果表明:采用渐进式进给成形方式时,旋压成形缺陷最少,但所获得的轮齿饱和度仅为70.2%;采用正反转式成形方式时,成齿区易出现预成形齿顶与旋轮轮齿啮合错位而导致被两次分形的缺陷;采用间歇式进给式成形方式时,成齿区齿顶部分出现大量毛刺;采用渐进式成形方式,相同试验条件下,通入脉冲电流后,材料塑性变形能力显著提升,轮齿饱和度提高到95.7%。采用电流辅助分形旋压成形获得的小模数齿形件齿廓偏差为0.029 mm、齿距偏差为0.015 mm。

Aiming at the problems of low material utilization and insufficient toughness of small modulus toothed parts made of difficult-to-deformed metals manufactured by traditional gear hobbing and gear shaping methods,the splitting spinning method was proposed to realize the complete near net forming of small modulus toothed parts.Taking the 30CrMnSiA alloy structural steel small modulus toothed parts with modulus of 0.3 as the research object,the splitting spinning forming process device for small modulus toothed parts made of difficult-to-deformed metals was designed and produced,the influence laws of three different forming methods of incremental feeding,forward and reversed feeding rotation of mandrel,intermittent feeding,as well as the conditions with/without current-assisted on the splitting spinning of small modulus toothed parts made of difficult-to-deformed metals were study based on the spinning forming experiments.The results show that the forming defects are the lowest when the incremental feeding forming method is adopted,but the saturation of gear teeth is on-ly 70.2%;twice splitting defect caused by the meshing misalignment between the preformed tooth and the roller tooth at the forming area occurs easily when the forward and reversed feeding forming method is adopted;a large number of burrs in the tops of the tooth at the forming area occur obviously when the intermittent feeding forming method is adopted;the plastic deformation capacity of the material im-prove significantly by pulsed current under the same experimental conditions,the saturation of gear teeth is increased to 95.7%based on incremental feeding when adopting the current-assisted forming method.The tooth profile deviation of small modulus toothed parts obtained by the current-assisted splitting spinning method is 0.029 mm,and the tooth pitch deviation is 0.015 mm.