Tiny Flaws Research Of Ultrasound Scattering Test Methods

Because of the reasons of preparation technology and circumstances, Somewelding methods, such as electron beam welding, are easily appear some tiny flaws(forexample: sharp spike、cold shut and line of solidification) and surface flaws which is invertical projection. These are the most damage to for welding splice, and those flawsreduce the piece useful time. Culture technology of Non-destructive testing is difficultto test these tiny flaws effective, so a new test technology is necessary. Based on theactual requirement and research situation at home and abroad, this paper do some testson different flaws in pieces, using ultrasound scattering method and model ofPitch-immersion, which will receive A-scan of flaws from different direction. Thepaper finally achieves automatic checkout purpose through scattering imaging device.The first, On the basic of acoustic, the paper states the propagation characteristicof sound wave in solid dielectrics, and than, it research the principle and method ofscattering wave test through the analysis of scattering sound filed of rigid round.The second, Basic on the feacture of different types of ultrasound scattering, thispaper researches and proves the distribution of scattering. All of these help us to studya set of technology problems, such as tilt angle、how far from object in water、excitiveand resive.The third, there is a requirement that ultrasound scattering test should combinewith practical situation, so the paper change add a new ultrasound scattering image testplatform enquitment to original one. This is the guaranty of the test.The last, I do some tests on the pieces of tiny flaws and get some images fromnew ultrasound scattering enquitment. The result shows ultrasound scattering methodcould calculate the tiny flaws and other flaws. This new method figure out a newresearch direction about Non-destructive testing technology that need higher sensitivity,such as electron beam welding.Compare with culture technology of Non-destructive testing, there are twoadvantages of ultrasound scattering technology:(1). It is propitious to surface flaws ontest pieces (because the place that reflection method can not checkout;(2). There is thehigh sensitivity for tiny flaws. Therefore, this research is so important for the furtherresearch of ultrasound scattering technology.