Research On The Technology Of Workpiece Defect Volume Visualization Based On Ultrasonic Testing

The flaw volume visualization technology of workpiece based on ultrasonic nondestructive testing is a new display technology which combines ultrasonic nondestructive testing technology and visualization technology.The technology can reconstruct the ultrasonic inspection data into three-dimensional image through a certain reconstruction algorithm,and can display the internal defects of the workpiece through the human-computer interaction interface,such as rotary,zooming,translation,perspective,cutting and so on,and quantitatively measure defects.The technology is an important means to quantitatively analyze and evaluate the effect of flaws in workpiece.Therefore,the research on the three-dimensional visualization of ultrasonic testing data,with a broad application prospects,has fatal research significance.In this paper,firstly,we summarize the development of the visualization technology of ultrasonic test,and the principles of ultrasonic detection,visualization,3D imaging,volume data structure and defect measurement are learned.Then,some key techniques in the visualization of ultrasound were studied.Aiming at the problem that the amount of ultrasonic data is too large,we propose a compression algorithm which can reduce the amount of data and meet the precision requirement.Aiming at the problem that ultrasonic can not distinguish between air and workpiece in the process of propagation,we propose an ultrasonic information enhancement method that help volume data image well.Aiming at the problem of quantitative measurement of defects,we propose a defect quantitative algorithm is that can calculate the volume,area and height of defect.Finally,we develop a set of ultrasound visualization system software to achieve the goal of the three-dimensional visualization of the ultrasonic testing data and the quantitative measurement of the defects.The software mainly includes six modules: data reading and storage,data processing,3D imaging,cutting,3D boundary extraction and flaw recognition,and flaw quantitative measurement.At the end of this paper,we use the ultrasonic microscopy equipment to scan the self-made three-hole of fat bottom test block.Under different scanning precision and different compression ratio,we analyze and compare the effect of imaging,the time of imaging and the result of quantitative measurement,which verify the feasibility of the visualization and quantitative measurement of the ultrasonic nondestructive testing.