Trial-Manufacture and Experimental Study of Particle Damping Boring Bar for Deep Hole Boring of 7075 Aluminum Alloy  

基于7075铝合金深孔镗削的颗粒阻尼减振镗杆试制与实验研究

作　　者：HUANG Yi HAN Jianxin DONG Qingyun 黄仪;韩建鑫;董庆运(天津职业技术师范大学机械工程学院,天津300222;天津市高速切削与精密加工重点实验室,天津300222;天津职业技术师范大学工程实训中心,天津300222)

机构地区：[1]School of Mechanical Engineering,Tianjin University of Technology and Education,Tianjin 300222,P.R.China [2]Tianjin Key Laboratory of High Speed Cutting and Precision Machining,Tianjin 300222,P.R.China [3]Engineering Training Center,Tianjin University of Technology and Education,Tianjin 300222,P.R.China

出　　处：《Transactions of Nanjing University of Aeronautics and Astronautics》2025年第1期123-136,共14页南京航空航天大学学报(英文版)

基　　金：supported by the Scientific Research Program of Tianjin Education Committee(No.2022ZD030)。

摘　　要：7075 aluminum alloy is often used as an important load-bearing structure in aircraft industry due to its superior mechanical properties.During the process of deep hole boring,the boring bar is prone to vibrate because of its limited machining space,bad environment and large elongation induced low stiffness.To reduce vibration and improve machined surface quality,a particle damping boring bar,filled with particles in its inside damping block,is designed based on the theory of vibration control.The theoretical damping coefficient is determined,then the boring bar structure is designed and trial-manufactured.Experimental studies through impact testing show that cemented carbide particles with a diameter of 5 mm and a filling rate of 70% achieve a damping ratio of 19.386%,providing excellent vibration reduction capabilities,which may reduce the possibility of boring vibration.Then,experiments are setup to investigate its vibration reduction performance during deep hole boring of 7075 aluminum alloy.To observe more obviously,severe working conditions are adopted and carried out to acquire the time domain vibration signal of the head of the boring bar and the surface morphologies and roughness values of the workpieces.By comparing different experimental results,it is found that the designed boring bar could reduce the maximum vibration amplitude by up to 81.01% and the surface roughness value by up to 47.09% compared with the ordinary boring bar in two sets of experiments,proving that the designed boring bar can effectively reduce vibration.This study can offer certain valuable insights for the machining of this material.7075铝合金因其优越的力学性能,常被用作航空工业中的重要承力结构。在深孔镗削过程中,由于加工空间有限、环境恶劣以及大伸长率导致刚度低,镗杆容易振动。为了减少振动、提高加工表面质量,基于振动控制理论设计了一种内部阻尼块填充颗粒的颗粒阻尼镗杆。然后确定了理论阻尼系数,设计并试制了镗杆结构。通过冲击试验研究表明,直径为5 mm、填充率为70%的硬质合金颗粒可实现19.386%的阻尼比,具有出色的减振能力,可能降低镗削振动的可能性。接着,设置了实验以探究其在7075铝合金深孔镗削过程中的减振性能。为了更明显地观察,采用了恶劣的工作条件进行实验,以获取镗杆头部的时间域振动信号以及工件的表面形貌和粗糙度值。通过比较不同实验结果,发现与普通镗杆相比,设计的镗杆在两组实验中可将最大振动幅度降低高达81.01%,表面粗糙度值降低高达47.09%,证明了设计的镗杆能有效减少振动。本研究可为该材料的加工提供一些有价值的见解。

关 键 词：7075 aluminum alloy boring bar vibration reduction particle damping 

分 类 号：TG713[金属学及工艺—刀具与模具]