压合衬套冷挤压对耳片孔表面性能的影响

文章以 7050 铝合金耳片孔为研究对象, 探究压合衬套冷挤压强化对耳片孔表面性能的影响, 通过三坐标测量仪、粗糙度仪、X 射线应力测定仪、金相显微镜等仪器对孔壁表面完整性进行分析。结果表明: 强化后耳片孔试样发生了塑性形变, 孔的内径增大; 随着相对挤压量增大, 残余压应力峰值和应力层深度也随之增大; 在相对挤压量为 2.5% 时, 挤出端残余压应力最大值为 -384.2 MPa, 并形成了约 14 mm 残余压应力层; 在同一相对挤压量下, 挤出端残余压应力高于挤入端; 塑性变形层中的晶粒显著细化。

Taking 7050 aluminum alloy lug hole as the research object, the effect of cold extrusion strengthening of press-fit bushing on the surface properties of lug hole was studied. The surface integrity of the hole wall was analyzed by coordinate measuring machine(CMM), roughness meter, X-ray stress analyzer, metallographic microscope and other instruments. The results show that after strengthening, the sample of lug hole undergoes plastic deformation and the inner diameter of the hole increases. With the increase of relative extrusion amount, the peak value of residual compressive stress and the depth of residual stress layer also increase. When the relative extrusion amount is 2.5%, the maximum residual compressive stress at the outlet end is -384.2 MPa, and formed a residual compressive stress layer of about 14 mm. Under the same relative extrusion amount, the residual compressive stress at the outlet end is higher than that at the inlet end. The grain in the plastic deformation layer is significantly refined.