Centre for Nondestructive Evaluation and Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
Ultrasonics. 2011 Aug;51(6):675-82. doi: 10.1016/j.ultras.2011.01.009. Epub 2011 Feb 2.
This paper presents a new method of improving the ultrasonic signal amplitude from a meander line EMAT by using soft magnetic alloy ribbon (Fe₆₀Ni₁₀V₁₀B₂₀) as a magnetic flux concentrator (MFC). The flux concentrator is a thin soft amorphous magnetic material (Fe₆₀Ni₁₀V₁₀B₂₀) which is very sensitive to a small flux change. The MFC is used with the EMAT to improve the signal amplitude and it was observed that the peak signal amplitude increases by a factor of two compared to the signal without MFC. Two dimensional numerical models have been developed for the EMAT with MFC to quantify the improvement of the received signal amplitudes. Model calculations and experiments have been carried out for a wide range of ultrasonic frequencies (500 kHz-1 MHz) in different materials.
本文提出了一种新的方法，通过使用软磁合金带（Fe₆₀Ni₁₀V₁₀B₂₀）作为磁通集中器（MFC），来提高折线型电磁超声换能器（EMAT）的超声信号幅度。磁通集中器是一种薄的软非晶态磁性材料（Fe₆₀Ni₁₀V₁₀B₂₀），对小的磁通变化非常敏感。MFC 与 EMAT 一起使用，以提高信号幅度，结果观察到与没有 MFC 的信号相比，峰值信号幅度增加了一倍。已经为带有 MFC 的 EMAT 开发了二维数值模型，以定量评估接收信号幅度的提高。在不同的材料中，针对宽范围的超声频率（500 kHz-1 MHz）进行了模型计算和实验。
