压合衬套冷挤压对耳片孔残余应力分布的影响  

Effect of cold extrusion of press-fit bushing on residual stress distribution of lug hole

作　　者：陶梅生 黄海鸿[1] 刘儒军 殷超超 任勇 刘志峰[1] TAO Meisheng;HUANG Haihong;LIU Rujun;YIN Chaochao;REN Yong;LIU Zhifeng(School of Mechanical Engineering,Hefei University of Technology,Hefei 230009,China;State-owned Wuhu Machinery Factory,Wuhu 241007,China)

机构地区：[1]合肥工业大学机械工程学院,安徽合肥230009 [2]国营芜湖机械厂,安徽芜湖241007

出　　处：《合肥工业大学学报(自然科学版)》2025年第1期19-24,共6页Journal of Hefei University of Technology:Natural Science

基　　金：国家自然科学基金重点资助项目(U20A20295)。

摘　　要：文章利用压合衬套冷挤压工艺对7050铝合金耳片孔进行挤压强化,并采用X射线应力测定仪对残余应力进行检测,研究冷挤压强化对耳片孔残余应力分布的影响。实验结果表明:压合衬套冷挤压工艺使耳片孔产生了明显的残余压应力,并沿孔壁径向形成了一定深度的残余压应力层;相同相对挤压量下,挤出端残余压应力明显高于挤入端,且残余压应力值随着相对挤压量增大而变大;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。通过显微硬度计对强化后的试样进行检测,检测结果表明,强化后的试样沿孔壁径向形成了约4.5 mm的组织硬化层,最大显微硬度提升达到了18.1%。冷挤压强化后孔壁沿径向形成了残余压应力层和组织硬化层,提高了耳片孔抗疲劳性能。The 7050 aluminum alloy lug hole was subjected to extrusion strengthening through the press-fit bushing cold extrusion process,and the residual stress was detected by the X-ray stress analyzer.The influence of cold extrusion strengthening on the residual stress distribution of the lug hole was studied.The results showed that the press-fit bushing cold extrusion process generated significant residual compressive stress in the lug hole and formed a residual compressive stress layer of a certain depth along the hole wall radius.Under the same relative extrusion amount,the residual compressive stress at the outlet end was significantly higher than that at the inlet end,and the residual compressive stress increased with the increase of the relative extrusion amount.At a relative extrusion amount of 2.5%,the maximum residual compressive stress at the outlet end was-384.2 MPa,and the residual compressive stress layer was about 14 mm.The strengthened specimens were tested by microhardness tester,and the results showed that the strengthened specimens formed an microstructure hardening layer of about 4.5 mm along the hole wall radius,and the maximum microhardness increased 18.1%.After cold extrusion strengthening,the hole wall formed residual compressive stress layer and microstructure hardening layer,thereby improving the fatigue resistance performance of the lug hole.

关 键 词：冷挤压 压合衬套 相对挤压量 残余应力 显微硬度 

分 类 号：TG376.3[金属学及工艺—金属压力加工]