电磁耦合能作用下2A02叶片锻件的残余应力松弛

Residual Stress Relaxation of 2A02 Blade Forging Under Electromagnetic Coupling Energy

摘要:

针对航空大尺寸薄壁件因残余应力释放导致加工变形的行业问题，提出了一种电磁耦合处理的新型材料处理方法，并将其应用于调控压气机2A02铝合金叶片锻件的残余应力。研究了电、磁场工艺对锻件残余应力和力学性能的影响；并对材料组织开展准原位EBSD分析。结果表明，相较于单一物理场，电磁耦合处理对残余应力的松弛效果最显著，在磁场强度为1.5 T、电场强度为750 V/m时，叶片锻件残余应力最大降幅为53%。电磁耦合处理可以在不损害强度的情况下，改善铝合金塑性，在上述电磁场参数下，其伸长率提高14.3%，电阻下降4.9%。EBSD准原位分析表明，电磁耦合处理后，锻件的几何位错密度降低58.2%，小角度晶界减少，塞积的位错分散、湮灭，局部应变降低，宏观应力松弛。

Abstract:

A novel method of electromagnetic coupling treatment (EMCT) was proposed to control the residual stress of 2A02 aluminum alloy blade forging in compressor, aiming at solving the industrial problem of machining deformation of large-size thin-wall parts due to residual stress releasing. The effects of electric and magnetic field treatment on the residual stress and mechanical properties of forgings were studied. The microstructure was analyzed by quasi-in-situ EBSD. The results show that compared with a single physical field, the EMCT has the most significant relaxation effect on residual stress. When the magnetic field intensity is 1.5 T and the electric field intensity is 750 V/m, the maximum reduction of residual stress of blade forging is 53%. EMCT can improve the plasticity of aluminum alloy without damaging the strength. Under the above parameters, the elongation is increased by 14.3% and the resistance is decreased by 4.9%. EBSD quasi-in-situ analysis shows that after EMCT, the geometric dislocation density of forgings is reduced by 58.2%, the small-angle grain boundaries are reduced, the plug dislocations are dispersed and annihilated, the local strain is reduced, and the macroscopic stress is relaxed.