ULTRASONIC CHARACTERISATION OF ADDITIVELY MANUFACTURED AlSi10Mg USING TIME OF FLIGHT AND ATTENUATION CALCULATIONS

Additive manufacturing is a novel method for the production of different alloys, such as aluminum, titanium, stainless steel and other materials and alloys. With the increasing development in additive manufacturing, a demand for quality control has risen as well. Ultrasonic examination, a non-destructive evaluation (NDE) method, can be used for qualitative and quantitative measurements of defects common to additive manufacturing (such as pores and lack of fusion).

In this research, AlSi₁₀Mg Specimens were additively manufactured using SLM method with notches marking degrees around the perimeter. The samples, three of which were heat treated prior, were examined using the Archimedes method and pulse echo ultrasonic methods. A longitudinal Time Of Flight (TOF) measurement and Frequency Depended Attenuation (FDA) were performed, as well as an angle depended transverse wave measurement.

The transverse TOF measurement revealed a clear anisotropy of the material in the untreated and the heat treated samples, despite the fact that no preferred orientation was displayed on metallographic exams in the same heat treatment. The FDA showed an increase in the attenuation coefficient slope as the heat treatment temperature increase. The measured density reflected an increase in porosity volume at higher temperature.