摘要：
针对航空发动机涡轮叶片榫头渗铝污染后产生的尺寸偏大和力学性能下降的问题,采用水吹砂+振动光饰和水吹砂+喷丸强化+振动光饰两种复合方法对渗铝后的K403合金试样进行处理,研究复合方法对K403渗铝试样微观组织和力学性能的影响.对两种方法处理后试样的微观组织、渗铝层元素分布、物相组成、残余应力和疲劳寿命进行测试.结果表明:渗铝后,试样表面存在残余拉应力,渗铝层厚度约27.3 μm,主要相为[-NiAl和t-Cr;水吹砂+振动光饰处理后,试样表面产生了360MPa的残余压应力,试样的疲劳寿命提高了1.49倍;水吹砂+喷丸强化+振动光饰方法处理后,试样表层产生了较大的残余压应力,距离表面0.04 mm处残余压应力值最大,约为686 MPa,应力影响深度约0.2 mm,试样的疲劳寿命提高了3.44倍.%Aiming at the problems of increasing in dimension and reducing in mechanical properties caused by the aluminized pollution of the turbine blade tenon,two composite methods:water grit-blasting + vibration adorn polish and water gritblasting + shot peening + vibration adorn polish,were put forward to handle the samples.The effects of the two composite methods on the microstructure and mechanical properties of K403 aluminized samples were studied.The microstructure,element distribution,phase composition,residual stress and the fatigue life of the samples handled by the two methods were tested,respectively.The testing results show that residual tensile stress exists on the surface of the samples after aluminizing.The thickness of the aluminizing layer is about 27.3 μm,and the main phases of the aluminized layer surface are beta-NiA1 and alpha-Cr.After water grit-blasting + vibration adorn polish method,a residual compressive stress of about 360 MPa is introduced to the surface,and the fatigue life increases by 1.49 times.After water grit-blasting + shot peening + vibration adorn polish method,a large residual compressive stress is introduced to the surface.The residual compressive stress at the distance of 0.04 mm from the modified surface is the largest,about 686 MPa,with the stress depth of about 0.2 mm.The fatigue life of the treated samples increases by 3.44 times.
