Phase3D is working with commercial part manufacturer, Alloyed in the UK, to characterize part and build quality and determine how anomalies in a build cause defects in a part using the Fringe in-situ inspection system. One uncovered trend for metal powder bed fusion (PBF) is recoaters often accrue damage early in a build, which aligns with parts, leading to an increase in porosity. Below is a particularly interesting heightmap from a calibration build where a recoater streak impacted the part in every layer. The streak was caused by physical damage to the recoater blade which repeated on every layer in the build and had an average depth of 200 microns.
The prediction that the repetitive streak would lead to a failure in the self-healing property of metal PBF was confirmed. This resulted in increased porosity formation along the streak. The video below shows how the CT scanned part has a clear line of increased porosity corresponding to the area impacted by the recoater streak.
A major concern brought up through this study is this clearly-identified anomaly in the heightmap which is not noticeable in the visual spectrum as shown in the image below. In the heightmap data, this streak can be seen impacting the uniformity of the melted layer, actively causing an underbuilt region on affected parts at every layer.
Heightmaps from Phase3D enable operators to make conclusions in minutes that would otherwise take hours and expensive, nondestructive testing (NDT) to make using traditional techniques. With Fringe, an operator can see exactly where, when, and how recoater damage occurs. Understanding build anomalies with quantifiable data enables a tighter feedback cycle for diagnosing problematic parts, build parameters, or recoater-part interactions, allowing companies to save time and money in their development and production process.
