Additive manufacturing processes have become commercially available and are particularly interesting for the production of free-formed parts. Selective laser melting allows to manufacture components by localized melting of successive layers of metal powder. In order to be able to describe and to understand the complex dynamics of selective laser melting processes more accurately, online measurements using ultrasound have been performed for the first time. In this contribution, we report on the integration of the measurement technique into the manufacturing facility and on a variety of promising monitoring results
The evaluation of residual stresses using ultrasound can be a very complex issue, because different material properties may effect the propagation of ultrasonic waves. Nevertheless, in the manufacturing of modern aero engines it is essential to benefit from the full potential of the employed materials. In this context, it is indispensable to test whether ultrasonic stress measurement is applicable for the highly developed nickel- and titanium-based alloys. This contribution contains basic investigations on the achievable measurement effect in samples made of Inconel IN718 and the Titanium alloy Ti 6-2-4-6. Furthermore, we give an overview over the principles of ultrasonic stress measurement using bulk and Rayleigh waves and present first results which are discussed with respect to texture effects and future work
The failure of propulsion components of ships and ferries can lead to serious environmental and economic damage or even the loss of lives. For ultrasonic inspection of such large components we employ mechanized scanning and defect reconstruction using the Synthetic Aperture Focusing Technique (SAFT). We report on results obtained in view of the detection of defects with different inspection techniques. Also, we address the issue of Probability of Detection by reporting results obtained in POD and MAPOD-studies (Model-Assisted POD) using experimental and simulated data. Finally, we show recent results of surface and sub-surface inspection using optical and eddy current techniques
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