摘要
近年来,随着冶金、航空、造船、建筑等工业的发展,对一些受力复杂、工作条件苛刻的构件和零件提出了越来越高的要求。为保证产品质量、降低生产成本和确保工程安全,对落砂铸件进行缺陷在线检测具有非常重要的实际意义。
本文基于音频检测原理构建了可实现铸件缺陷快速检测的音频检测系统。介绍了音频检测铸件缺陷的原理,对铸件缺陷与音频能量衰减和音频共振频率的关系进行了详细评述,在音频信号中提取共振频率与内耗作为铸件缺陷识别的主要参数。该系统具有测试装置简单、测试速度快和准确度高等特点。
音频检测系统主要由脉冲激励装置、音频传感器、信号调理电路、数据采集卡和微型计算机等部分组成。采用具有固定势能的硬质小钢球向被测铸件提供脉冲激励,选用驻极体传声器作为音频传感器,利用计算机声卡作为音频信号的采集硬件。通过MATLAB提供的数据采集工具箱(Data Acquisition Tool)进行信号采集,并将音频信号数据存储到计算机中,利用信号处理工具箱对采集到的音频信号进行包括消除信号趋势项、平滑处理、数字滤波等处理,最终提取音频信号的特征参数,实现对铸件缺陷的快速识别。
初步实验结果证明,本文设计的音频检测系统可用于铸件缺陷无损检测,具有方法简单、硬件成本低、识别准确等优点。
In recent years, with the development of metallurgy, aviation, shipbuilding, architecture and other industries, higher requirements for components and spares which worked under complex loading conditions have arisen. To ensure the product quality, reduce the costs and guarantee the engineering safety, it has very important practical significance to online monitor the defects of castings.
According to the resonant acoustic principle, a nondestructive inspection system of fast detecting the casting defects is constructed in this paper. On the basis of introducing the principle of the detecting the casting defects, the relations between acoustical energy attenuation, acoustic resonance frequency and the casting defects are described in detail, and thus resonant frequency and internal friction values of castings from acoustic signal are taken as the main parameters of identifiying the casting defects. The system has the merits of simple measurement device, fast measurement speed and high accuracy.
The audio frequency inspection system is mainly composed of the impulse excitation device, acoustic sensor, signal conditioning circuits, data acquisition card and micro-computer and so on. Small hard steel spheres with fixed gravity potential energy are used as impulse exciter, the electrets condenser microphone is used as acoustic sensor, and computer sound card is used as the acoustic signal acquisition hardware. The data of acoustic signal are collected by the Data Acquisition Toolbox of Matlab, and the results are automatically stored by computer. After eliminating signal trend, smoothing signal curves and digital filter, characteristic parameters are got and thus the defects of the castings are fast indentified.
The preliminary experimental results show the audio frequency inspection system can be used to nondestructive detect of the casting defects and the system has the advantages of simple opration, low-cost hardware and high accuracy.
引文
[1]王自明.无损检测综合知识[M].北京:机械工业出版社, 2005: 96-98.
[2]徐丽,刚铁,张明波,等.铸件缺陷无损检测方法的研究现状[J].铸造, 2002, 51(9): 535-540.
[3]乐书华,王怡之,张寿柏,等.无损检测在铸件上的应用概况[J].中国铸造装备与技术, 1981, (1): 34-40.
[4]刘晴岩.液体渗透检测的可靠性[J].无损检测, 2002, 24(9): 381-383.
[5]聂小武,鲁世强,王克鲁.铸锻件磁粉与渗透检测工艺的选择[J].铸造, 2006, 55(4): 387-389.
[6]周乐,张志文.无损检测及其新技术[J].重庆工学院学报, 2006, 20(8): 46-48.
[7]聂小武,鲁世强,王克鲁.铸件磁粉检测缺陷分析及预防[J].铸造, 2006, 55(10): 1056-1059.
[8]黄建明,林俊明.焊缝电磁涡流检测技术[J].无损检测, 2004, 26(2): 95-98.
[9]美国无损检测学会编.美国无损检测手册(电磁卷)[M].上海:世界图书出版公司, 1999: 262-269.
[10]无损检测学会编.射线检测[M].第3版.北京:机械工业出版社, 2003: 124-125.
[11]徐丽,张幸红,韩杰才.射线检测在复合材料无损检测中的应用[J].无损检测, 2004, 26(9): 450-456.
[12]刘贵明.无损检测技术[M].北京:国防工业出版社, 2005: 10-11.
[13]刘福顺,汤明.无损检测基础[M].北京:北京航空航天大学出版社, 2005: 86-87.
[14]美国无损检测学会.美国无损检测手册(超声卷)[M].上海:世界图书出版公司, 1996: 49-50.
[15]无损检测学会编.声发射检测[M].北京:机械工业出版社, 2003: 7-8.
[16]王俊涛,宋永伦,王淑洁.声发射缺陷检测技术的应用与发展[J].机床与液压, 2004, (4): 4-5.
[17]刘莹,张记龙.材料的红外无损检测技术及其进展[J].华北工学院测试技术学报, 2001, 15(4): 275-279.
[18]王仲生.无损检测诊断现场实用技术[M].北京:机械工业出版社, 2002:35-36.
[19] FULLER A G, EMERSON P J, REW R. Sonic Testing a Simple Nondestructive Testing for Verifying Casting Quality[J]. BCIRAJournal, 1963, (11): 358-375.
[20] KOVACS B V, COLE G S. On the Interaction of Acoustic Waves with SG Iron Castings[J]. Transactions of the American Foundrymen's Society, 1975, 83(74): 497-502.
[21] EMERSON P J, SIMMONS W. Final Report on the Evaluation of the Graphite Form in Ferritic Ductile Iron by Ultrasonic and Sonic Testing and of the Effect of Graphite Form on Mechanical Properties[J]. Transactions of the American Foundrymen's Society, 1977, 84(81): 109-128.
[22] KOVACS B V, STONE J, PAPADAKIS E P. Development of an Improved Sonic Resonance Inspection System for Modularity in Crankshafts[J]. Materials Evaluation, 1984, 42(7): 906-916.
[23] ABBOTT J A, MASSIE D R, UPCHURCH B L. Nondestructive Sonic Firmness Measurement of Apple[J]. Transactions of the ASAE, 1995, 38(5): 1461-1466.
[24] FOLEY, DAVID F. Resonant Inspection - a Promising NDT Option[J]. Metal Powder Report, 1996, 51(10): 4-5.
[25] FOLEY, DAVID K. Resonant Inspection: An NDT Tool That Keeps Getting Easier to Use[C]. Metal Powder Industries Federation. Proceedings of the 1997 International Conference on Powder Metallurgy and Particulate Materials. Chicago, 1997: 83-86.
[26] HONARVAR F, SINCLAIR A N. Nondestructive Evaluation of Cylindrical Components by Resonance Acoustic Spectroscopy[J]. Ultrasonics, 1998, 36(8): 845-854.
[27] KIM J T, STUBBS N. Crack Detection in Beam-Type Structures Using Frequency Data[J]. Journal of Sound and Vibration, 2003, 259(1): 145-160.
[28] HERTLIN I. Acoustic Resonance Analysis[M]. Chicago: Castell Publication Inc., 2003: 32-35.
[29] HERTLIN I. Acoustic Resonance Analysis Using FEM and Laser Scanning For Defect Characterization in In-Process NDT. Chicago: ECNDT, 2006[2006-9-15]. http://www.ndt.net/article/ecndt2006/doc/We.4.8.1.pdf.
[30]孙国桢.锤击法自动检测技术[J].检测与评价, 1983, (4): 4-6.
[31]柏逢明.音频检测技术与仪器[M].北京:国防科学出版社, 2006: 4-5.
[32]徐光清.汽车排气管蠕化率的音频检测[J].无损检测, 1987, (9): 241-244.
[33]方京,陈礼光,游凤荷,等.球墨铸铁件质量无损检测方法研究的进展[J].武汉工学院学报, 1990, 12(2): 45-51.
[34]姚方中,宓中玉,顾林富.声波扫频法自动检测球墨铸铁球化质量[J].无损检测, 1989, 13(1): 5-8.
[35]陈国贤.无损检测技术在二汽厂的应用及效果[J].无损检测, 1990, (3): 76-77.
[36]柏逢明.球墨铸铁内在质量音频检测方法研究[J].长春光学精密机械学院学报, 1993, (4): 17-23.
[37]柏逢明,马莉,潘毓学,等.弹体药室容积音频检测仪的研制[J].兵工学报, 1999, 20(1): 19-23.
[38]夏东志,史耀武,陈建忠,等.热喷涂涂层声振检测[J].无损检测, 1999, 21(6): 260-262.
[39]徐秀芳,胡晓东,陈良益,等.用于CA488轻型车凸轮轴的音频无损检测系统[J].西安交通大学学报, 2000, 34(11): 104-105.
[40]杨通强,唐力伟,郑海起,等.基于声测法的齿轮箱齿轮故障诊断研究[J].军械工程学院学报, 2000, 12(4): 24-27.
[41]彭永恒,陈静云,潘宝峰,等.声振法对刚性路面板脱空状况检测应用的研究[J].公路交通科技, 2005, 22(3): 54-57.
[42]吴伟,彭永恒,朴泽星,等.声振法混凝土路面的声学特征检测研究[J].哈尔滨商业大学学报:自然科学版, 2005, 21(4): 509-511.
[43]孙磊,赵鸣.基于音频检测技术的混凝土无损检测技术[J].福州大学学报:自然科学版, 2005, 33(S1): 228-232.
[44]周景亮,林志熙,黄耀志.应用声振法对轴承滚子无损检测的研究[J].机械设计制造, 2006, (4): 36-37.
[45]柏逢明,马莉,潘毓学,等.音频检测技术及发展动态[J].长春光学精密机械学院学报, 1998, 21(3): 95-99.
[46]柏逢明.音频检测技术与仪器[M].北京:国防科学出版社, 2006: 45-49.
[47]徐云峰.基于声卡动态测试信号采集与处理系统的研究[D].江苏大学:硕士论文, 2006: 22-23.
[48]胡广书.数字信号处理:理论、算法与实现[M].北京:清华大学出版社, 1997: 125-129.
[49]蒋志凯.数字滤波与卡尔曼滤波[M].北京:中国科学技术出版社, 1993, 59-65.
[50]楼顺天,李博菡.基于MATLAB的系统分析与设计——信号处理[M].西安:西安电子科技大学出版社, 1998: 59-62.
[51]罗军辉,白义巨. MATLAB7.0在数字信号处理中的应用[M].北京:机械工业出版社, 2005: 87-99.
[52]王济,胡晓. MATLAB在振动信号处理中的应用[M].北京:中国水利水电出版社, 2006: 83-100.
[53]李亚微,郭敏.基于MATLAB的音频数据采集系统[J].电声技术, 2007, 31(3): 57-58.