Kannajosyula Surya Prakash, Chillara Vamshi Krishna, Balasubramaniam Krishnan, Krishnamurthy C V
Department of Mechanical Engineering, Centre for Nondestructive Evaluation, IIT Madras, Chennai 600 036, India.
Rev Sci Instrum. 2010 Oct;81(10):105101. doi: 10.1063/1.3494612.
A measurement technique has been developed to extract the phase information of successive echoes for the simultaneous estimation of thicknesses and ultrasonic velocities of individual layers in a two layered media. The proposed method works in the absence of an interface echo and requires the total thickness of the sample to be known. Experiments have been carried out on two layered samples of white cast iron and gray cast iron with layer thickness variation in the range of 2-8 mm for total thickness variation in the range of 12-13 mm. Comparison with micrographs of a few samples confirmed the model predictions. The model is found to be sensitive to the total sample thickness but fairly insensitive to noise in the data.
已开发出一种测量技术，用于提取连续回波的相位信息，以便同时估计双层介质中各层的厚度和超声速度。该方法在无界面回波的情况下有效，且需要知道样品的总厚度。已对白色铸铁和灰色铸铁的双层样品进行了实验，层厚度变化范围为2 - 8毫米，总厚度变化范围为12 - 13毫米。与一些样品的显微照片比较证实了模型预测。发现该模型对样品总厚度敏感，但对数据中的噪声相当不敏感。
