Measurement of Residual Stress Using Magnetic Barkhausen Noise Analysis
Measurement of Residual Stress Using Magnetic Barkhausen Noise Analysis
复制标题
使用磁巴克豪森噪声分析测量残余应力
DOI：
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发表时间：
1975
期刊：
影响因子：
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通讯作者：
C. G. Gardner
中科院分区：
文献类型：
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作者：
G. Matzkanin;C. G. Gardner
在本文中，我们简要地回顾了用巴克豪森效应进行应力测量的概念，并列举了其实际应用的主要实例;本文的主要部分介绍了最近获得的一些关于塑性变形和双轴应力场效应的结果。材料科学与工程学院|结构和材料这10.残余应力可从爱荷华州州立大学数字资料库：http://lib.dr.iastate.edu/cnde_yellowjackets_1975/获得。A. Matzkanin和C. G.加德纳西南研究所圣安东尼奥，得克萨斯州在这篇演讲中，我们非常简要地回顾了涉及的概念，通过巴克豪森效应的应力测量，并列举了其实际应用的主要实例;该文件的主要部分是专门介绍一些最近获得的结果，塑性变形的影响，和双轴应力场。确定铁磁材料中残余应力的巴克豪森噪声分析方法基于众所周知的事实，即磁化强度以称为巴克豪森跳跃的突然、不可逆增量变化。这在图1中示出，图1示出了典型的磁滞回线的一部分在适当灵敏的检测方法下看起来是什么样子。巴克豪森跃变主要发生在磁滞回线的陡峭部分，并且主要与180°畴壁的移动有关。伴随着巴克豪森跳跃的磁通量的快速变化能够在感应耦合到样品的检测线圈中感应电压脉冲，如图2中的示波器照片所示。这些脉冲在幅度、持续时间和时间间隔上有些随机，可以粗略地描述为“噪声”，因此称为巴克豪森噪声。存在用于检测和研究巴克豪森噪声现象的若干替代方法。归纳方法可以从模拟或数字的角度来处理。这是迄今为止开发的实际仪器所使用的模拟方法。框图如图3所示。一个C形磁铁是用来产生一个随时间变化的磁场在表面的试样和一个小线圈放置在接近试样表面是用来检测的巴克豪森噪声电压。滤波用于选择感兴趣的期望频率范围，通常从1 kHz到10 kHz或更高。通过检测由样品磁化的单个反转产生的巴克豪森脉冲的突发的包络来获得模拟信号。该信号可以在仪表上显示或读出其峰值;示例如图4所示。图5所示为实际应力测量仪器的照片。分析巴克豪森噪声的另一种方法是使用多通道脉冲高度分析器对各个巴克豪森脉冲进行分类和计数。图6显示了一个典型的脉冲高度分布，从一个单一的硅-铁样品磁化反转。
In this presentation we very briefly review the concepts involved in stress measurement by means of the Barkhausen effect, and cite the major instances of its practical application; the major part of the paper is devoted to a presentation of some recently obtained results regarding the effects of plastic deformation, and of biaxial stress fields. Disciplines Materials Science and Engineering | Structures and Materials This 10. residual stresses is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/cnde_yellowjackets_1975/ 27 MEASUREMENT OF RESIDUAL STRESS USING MAGNETIC BARKHAUSEN NOISE ANALYSIS G. A. Matzkanin and C. G. Gardner Southwest Research Institute San Antonio, Texas In this presentation we very briefly review the concepts involved in stress measurement by means of the Barkhausen effect, and cite the major instances of its practical application; the major part of the paper is devoted to a presentation of some recently obtained results regarding the effects of plastic deformation, and of biaxial stress fields. The Barkhausen Noise Analysis approach to determining residual stress in ferromagnetic materials is based upon the well known fact that the magnetization changes in abrupt, irreversible increments called Barkhausen jumps. This is illustrated in Fig. 1 which shows what a portion of a typical hysteresis loop would look like with suitably sensitive detection methods. Barkhausen jumps occur mainly in the steep part of the hysteresis loop and are primarily associated with movements of 180° domain walls. The rapid changes in magnetic flux accompanying Barkhausen jumps are capable of inducing voltage pulses in a detection coil inductively coupled to the specimen, as shown in the oscilloscope photograph in Fig. 2. These pulses are found to be somewhat random in amplitude, duration, and temporal separation, and can roughly be described as "noise 11 ; hence the term Barkhausen noise. Several alternative methods exist for detecting and studying Barkhausen noise phenomena. The inductive method can be approached from either an analog or digital standpoint. It is the analog approach which the practical instrumentation developed to date has utilized. A block diagram is shown in Fig. 3. A C-shaped magnet is used to produce a time-varying magnetic field in the surface of the specimen and a small coil placed in proximity to the specimen surface is used to detect the Barkhausen noise voltage. F~ltering is used to select the desired frequency range of interest, generally from 1 kHz to 10 kHz or higher. An analog signal is obtained by detecting the envelope of the burst of Barkhausen pulses resulting from a single reversal of the specimen magnetization. This signal can be displayed or its peak value read out on a meter; an example is shown in Fig. 4. A photograph of a practical stress measuring instrument is shown in Fig. 5. Another approach to analyzing Barkhausen noise is to use a multichannel pulse height analyzer to sort and count the individual Barkhausen pulses. Figure 6 shows a typical pulse height distribution resulting from a single reversal of magnetization for a silicon-iron specimen.