Layer-by-Layer Non-Destructive Testing of Metal 3D Printed Objects

Background:

Selective laser melting has grown in popularity due to the advances in 3D printing of metal objects. It allows for layer-by-layer construction of parts that would previously have been either impossible or too expensive to produce using traditional manufacturing techniques. However, voids can form due to incomplete melting, metal vaporization or from the pressure produced during vaporization of the metal.

 Technology Overview:

This technology is being developed to allow for the non-destructive testing of metal printed parts layer-by-layer during the build process. This would allow for correction of voids while it is being printed, instead of printing a new part to replace it.

 Advantages:

 

• IR thermography can detect certain defects, but is less refined spatially. The benefit of this periodic thermoreflectance based technique is a sensitivity to just a layer into the material, by controlling the frequency of the laser input. This system can use the existing laser used to melt material.