为解决航空发动机压气机一级转子叶片在制备全流程中残余应力难以控制的问题,基于Simufact平台对该TC4钛合金叶片进行了包含3次顶锻-预锻-终锻-切边-校正-退火及各工步转运过程在内的全流程有限元计算,获得了该叶片在制备各环节中的残余应力变化趋势。通过小孔法实测了叶片锻件成品中叶身、榫头及其衔接处3个特征位置的残余应力,并与全流程有限元计算结果进行比对,验证了所建立的计算模型的准确性。通过定量分析制备各环节的残余应力变化,确定了终锻为残余应力累积最主要的阶段,退火处理为残余应力消减最主要的阶段,探究了终锻和退火处理的关键因素如锻造速度、锻造温度与退火温度对残余应力的影响规律,并结合正交试验优化了相关工艺参数。结果表明:随终锻锻造速度的增加,锻件残余应力呈下降趋势;锻造温度升高使最终残余应力先增后减;退火温度升高可促进残余应力释放,但需兼顾β相析出对性能的影响。正交试验显示各参数对残余应力的影响程度为退火温度>锻造温度>锻造速度,优选工艺组合为锻造温度958℃、锻造速度160 mm·s^-1、退火温度730℃。

To address the issue of difficult-to-control residual stress in the first-stage rotor blades of aero-engine compressors throughout the full preparation process, full-process finite element calculations of TC4 titanium alloy blades based on the Simufact platform were conducted. The calculations include triple upsetting, pre-forging, final forging, trimming, sizing, annealing, and the transportation process between each step, obtaining the residual stress variation trends of the blades at each preparation stage. The residual stresses at three characteristic locations—the blade body, the dovetail and their connection—were measured in the forged finished blades using the holedrilling method and compared with the full process finite element results, verifying the accuracy of the established calculation model. By quantitatively analyzing the residual stress changes at each preparation stage, it was determined that the final forging is the primary stage of residual stress accumulation, while annealing is the main stage for its reduction. The influences of key factors during final forging and annealing, such as forging speed, forging temperature and annealing temperature on residual stress were investigated, and related process parameters were optimized through orthogonal experiments. The results indicate that with the increase of the final forging speed, the residual stress of the forging decreases; increasing the forging temperature causes the final residual stress to first increase and then decrease; increasing the annealing temperature promotes residual stress release, although the impact of β-phase precipitation on properties must be considered. Orthogonal experiments show that the influence of each parameter on residual stress follows the order: annealing temperature > forging temperature > forging speed. The optimal process combination is the forging temperature of 958 ℃, the forging speed of 160 mm·s^-1, and the annealing temperature of 730 ℃.