By adopting electropolishing processes, Macfab has further enhanced its precision machining operations. Performing this process in-house reduces issues that can arise from handling and transport, and the vertical integration allows us to deliver finished, ready-to-use parts to our customers.
While tumbling, vibration, and hand deburring are effective processes and generate marginal improvements in surface finish, electropolishing is a superior method. It ensures a precision finish at the microscopic level and burr removal for parts. Electropolishing is generally only performed at tight tolerance and precision machining facilities, such as MacFab. This process was developed in the 1950s. During the years since its development, it has also been called electrochemical polishing, anodic polishing and electrolytic polishing.



The Electropolishing Process
The electropolishing process delivers a broad enhancement to parts. The parts are first loaded onto a metallic tree or fixture for good electrical contact. The fixture is then connected to the positive side of a Direct Current (DC) circuit, making the parts the anode of the reaction. A second metallic plate is submerged in the tank and connected to the negative side of the DC circuit. The tank is filled with an electrolytic solution matched to the part’s material.
Electricity is then applied to the workpiece so the solution breaks the bonds of the stainless steel atoms. Imagine having a small lightning bolt pass through the burr or high points on the part’s surface. What is left is a metallic salt. The part is now burr-free, with an improved surface finish at the same time.
Below are a few of the industry standards covering electropolishing that Macfab uses in developing and controlling our process.
ASME BPE
Standards for Electropolishing
Bioprocessing Equipment
SEMI F19
Electropolishing Specifications for
Semiconductor Applications
ASTM B912
Passivation of Stainless Steels Using
Electropolishing