Metal finishing companies in Massachusetts offer a wide range of different possibilities for finishing various metals and alloys. One of the most commonly used for a wide range of different types of metals and alloys is electropolishing.
This process can be used with aluminum and it is one of the most effective ways to bring out a bright, smooth and reflective surface on most aluminum alloys. As it is a chemical finish, it can be used on even the most complex and irregular parts and component to create a surface to extremely tight tolerances.
It is also the process used with steel, stainless steel, copper and brass. The result of applying this chemical finish to an alloy is to smooth out the surface of the metal to a microstructural level as well to clean and deburr the component, part or piece in one operation that can be controlled to the specifications of the customer.
How it Works
As mentioned above, electropolishing is a chemical process and not a mechanical or manual way to prepare the surface. It is the opposite process to electroplating, which distributes a layer or coating of a material on the surface of a metal where it binds to provide corrosion resistance and improve the aesthetics of the piece.
With the electropolishing process , the part is submerged in a bath of liquid of what is known as an electrolyte. This is an electrically conductive solution that is a mixture of the electrolyte and water. The part in the liquid is the anode in the process.
A current passes from the anode through the solution to the cathode, which is also in the bath. This movement of the current causes the metal on the microscopic “peaks” on the surface to oxidize and then dissolve into the bath where the move to the cathode.
The result is that the surface peaks, which extremely small, are dissolved at a higher rate than those in the connecting “valleys” on the surface. This results in the peaks being dissolved at a much faster rate than the rest of the metal, leaving a smoother surface.
Different voltages, temperatures and even the stirring action used in the electrolyte bath are carefully selected based the specific requirements for each job. The specific composition of the bath is also a critical decision.
This makes the process idea for any shape of part as the liquid can move about freely in spaces where other types of finishing would not be possible. The process also removes the edges from the surface cuts and corners, a process known as deburring.