Wednesday, 1 June 2022: 15:00
West Meeting Room 206 (Vancouver Convention Center)
To improve the interchangeability of additively manufactured (AM) metal components with traditionally
wrought or machined parts, there is a need for new surface finishing methods that can address the rough,
“as-printed” surfaces, which can suffer from arithmetic mean asperity heights (Sa) in the tens of microns.
While traditional direct current electropolishing (EP) is a useful technique for improving roughness and
corrosion resistance, particularly for AM metal components with internal surfaces, this method is limited
to smoothing roughness features smaller than 1 μm in size. This treatment also requires removal of a
substantial amount of material, leading to changes in part geometry. Here, we present a scalable
pulse/pulse reverse (P/PR) EP technique for use on AM 316L stainless steel (SS) surfaces, where pulse,
intensity, timing, and electrolyte properties can be varied independently thus granting more control over
electrodynamic processes, such as concentration gradients at the part-electrolyte interface. Such control
enables quasi size-selective asperity removal that has been previously unattainable by traditional DC EP
methods. Here, a combined P/PR and DC EP technique is presented that successfully smooths AM 316L
SS surfaces to an arithmetic mean height (Sa) as low as 1.0 μm with minimal surface waviness.
Additionally, P/PR EP showed substantially higher smoothing efficiency, where a larger reduction in
roughness was achieved with considerably less material removed as compared to conventional DC EP.
wrought or machined parts, there is a need for new surface finishing methods that can address the rough,
“as-printed” surfaces, which can suffer from arithmetic mean asperity heights (Sa) in the tens of microns.
While traditional direct current electropolishing (EP) is a useful technique for improving roughness and
corrosion resistance, particularly for AM metal components with internal surfaces, this method is limited
to smoothing roughness features smaller than 1 μm in size. This treatment also requires removal of a
substantial amount of material, leading to changes in part geometry. Here, we present a scalable
pulse/pulse reverse (P/PR) EP technique for use on AM 316L stainless steel (SS) surfaces, where pulse,
intensity, timing, and electrolyte properties can be varied independently thus granting more control over
electrodynamic processes, such as concentration gradients at the part-electrolyte interface. Such control
enables quasi size-selective asperity removal that has been previously unattainable by traditional DC EP
methods. Here, a combined P/PR and DC EP technique is presented that successfully smooths AM 316L
SS surfaces to an arithmetic mean height (Sa) as low as 1.0 μm with minimal surface waviness.
Additionally, P/PR EP showed substantially higher smoothing efficiency, where a larger reduction in
roughness was achieved with considerably less material removed as compared to conventional DC EP.