The role of wet blasting in the post-processing of AM parts

30 May, 2023

As previously mentioned, depending on the specific wet blast process, the typical concentration of abrasive media in the slurry ranges from 10 to 40% by volume. Establishing the ideal concentration requires processing trials that are always best undertaken in collaboration with a technology expert.

Wet blasting for Additive Manufacturing

Wet blasting is an essential technology for various AM post processing tasks. Wet blasting cleans the 3D printed components by removing residual powder and significantly reduces their initial high surface roughness. It is capable of depowdering and providing general surface cleaning and initial surface smoothing from Ra 25 µm to 1–1.5 µm. The technology makes parts more homogeneous and therefore better prepared for effective mass finishing, which also takes less time once a part has been wet blasted.

On metal AM parts the loosely sintered grains on corners are effectively removed. The wet process eliminates the worry about residual powder containment or sparking during the blasting process.

Wet blasting can be applied to and provide numerous finishes to metal and non-metal parts alike. Different media and different blast intensity customises the surface finish achieved. In addition, many AM parts require coating or painting postbuild, and wet blasting creates what is called a “wet out” surface that allows the optimal adhesion of paints or coatings.

Changing media amount and blast intensity allows the effective cleaning and depowdering of a variety of plastic and metal AM parts with wet blasting. Often, AM parts have difficult to reach internal channels and complex geometries which are not well served by dry blasting technologies, but which are easily and demonstrably cleaned and completely depowdered using wet blasting.

Summary

While some companies expend huge resource on innovating bespoke postprocessing solutions for AM parts, industry is now waking up to the fact that a broad range of traditional finishing technologies can be easily adapted to post process AM parts. When looked at through the prism of exacting tolerance attainment, superior surface finish, applicability to delicate and geometrically complex parts, and repeatability, wet blasting is a compelling technology for the post-processing of AM parts and components while remaining adaptable and cost effective.

www.solutions-for-am.com

https://twitter.com/rosleruk

https://www.linkedin.com/company/r-sler-uk/