Another NDT technology

My last post addressed the advantage of eddy current for crack detection. It does have a couple of limitations though. The crack must be surface-breaking, or very near, and the material under inspection needs to be ferrous. So what if you need to look for flaws deeper under the surface?

Well the conventional options would be x-ray (expensive and raises safety concerns,) and ultrasound. Historically, ultrasound has been a single point pulse-echo technology, and so had to be scanned across a surface, making it slow. But I’m here to tell you that things are changing!

The new trend in ultrasound is the phased array. This “ … provides better imaging, higher repeatability and reproducibility and more angles and scan patterns over conventional ultrasonic methods.” That quote comes from “How Ultrasonic Phased Array is Shaping the Industry,” published on the NDTmag website July 28th, 2010. If you need to find flaws beneath a surface, this is something you ought to read.