锯切圆柱形42CrMoA的声发射监测试验  

Monitoring Experiment of Acoustic Emission of Sawing Cylindrical 42CrMoA

作　　者：陈冰 毕升豪 王健 邓朝晖[1] 刘国跃 CHEN Bing;BI Shenghao;WANG Jian;DENG Zhaohui;LIU Guoyue(School of Mechanical and Electrical Engineering,Hunan University of Science and Technology,Xiangtan 411201;Hunan Taijia New Material Technology Co.,Ltd.,Changsha 410203)

机构地区：[1]湖南科技大学机电工程学院,湘潭411201 [2]湖南泰嘉新材料科技股份有限公司,长沙410203

出　　处：《宇航材料工艺》2023年第4期88-96,共9页Aerospace Materials & Technology

基　　金：国家自然科学基金面上项目(No.52175401);湖南省研究生科研创新项目(QL20210239)。

摘　　要：针对锯切加工中的带锯条磨损状态未知、锯切质量下降等问题,本文研究了新试制的FTCUT双金属带锯条锯切圆柱形42CrMoA合金结构钢过程中锯切行为的变化,探讨了声发射信号与单刀锯切过程、锯齿磨损和锯切表面质量变化的关联。研究表明:锯切圆柱材料时随着锯切深度的变化,参与齿数先增大后减小,带锯条约束条件不断变化,进而影响着声发射信号幅值和锯切表面质量;基于时域分析可知锯齿磨损过程分为磨合磨损、快速磨损、稳定磨损三个阶段;基于FFT频域分析发现当频谱图出现多个主频,且第一主频幅值下降时,表明声发射信号来源比较分散,即可认定带锯条失效;基于小波包频域分析发现第7频段信号占比最高,最能反映工件表面质量的变化,其波动情况与锯切表面的微纹和波纹情况可建立一定的联系。因此,可基于声发射信号时域和频域分析判断锯齿磨损和锯切表面恶化情况,为锯齿磨损和锯切表面质量的在线监测提供一定的思路。In order to solve the problems of unknown bandsaw blade wear state and the deterioration of sawing quality in sawing process,the sawing behavior change of FTCUT bimetallic bandsaw blade during sawing of 42CrMoA alloy structure steel was studied and the relationship between acoustic emission signal and the single-blade sawing process,saw teeth wear and sawing surface quality change was discussed.The results indicate that with the change of sawing depth,the number of saw teeth increases first and then decreases and the constraints of the bandsaw change constantly,which affects the acoustic emission signal amplitude and sawing surface quality.Based on the time domain analysis,the saw teeth wear process can be divided into three stages:run-in wear,fast wear and stable wear.Based on the FFT frequency domain analysis,it is found that when there are multiple dominant frequencies in the spectrum diagram and the amplitude of the first dominant frequency decreases,the acoustic emission signal sources are scattered,and the bandsaw blade failure can be determined.Based on the analysis of wavelet packet frequency domain,it is found that the 7th frequency band signal has the highest proportion and can reflect the change of workpiece surface quality.A certain relationship can be established between the fluctuation and micro grain and ripple of the sawing surface.Therefore,the saw teeth wear and sawing surface deterioration can be analyzed and judged based on acoustic emission signal in time domain and frequency domain.A certain idea for online monitoring of saw teeth wear and sawing surface quality is provided.

关 键 词：声发射 时域分析 频域分析 小波包分解 锯齿磨损 在线监测 

分 类 号：TB332[一般工业技术—材料科学与工程]