Machining processes
Machining processes
ECM
Electrochemical machining (ECM) is a method of removing metal by an electrochemical process. It is normally used for mass production and is used for working extremely hard materials or materials that are difficult to machine using conventional methods.[1] Its use is limited to electrically conductive materials. ECM can cut small or odd-shaped angles, intricate contours or cavities in hardened exotic metals, such as titanium aluminised, Inconel, Waspalloy, and high nickel, cobalt, and rhenium alloys. Both external and internal geometries can be machined.ECM is often characterized as "reverse electroplating," in that it removes material instead of adding it.
In the ECM process, a cathode (tool) is advanced into an anode (work piece). The pressurized electrolyte is injected at a set temperature to the area being cut. The feed rate is the same as the rate of "liquefaction" of the material. The gap between the tool and the work piece varies within 80-800 micrometers (.003 in. and .030 in.) As electrons cross the gap, material from the work piece is dissolved, as the tool forms the desired shape in the work piece. The electrolytic fluid carries away the metal hydroxide formed in the process.
Advantages and Disadvantages
Because the tool does not contact the work piece, its advantage over conventional machining is that there is no need to use expensive alloys to make the tool tougher than the work piece. There is less tool wear in ECM, and less heat and stress are produced in processing that could damage the part. Fewer passes are typically needed, and the tool can be repeatedly used. Disadvantages are the high tooling costs of ECM, and that up to 40,000 amps of current must be applied to the work piece. The saline (or Acidic) electrolyte also poses the risk of corrosion to tool, work piece and equipment.
EDM
Electric discharge machining (EDM), sometimes colloquially also referred to as spark machining, spark eroding, burning, die
ECM
Electrochemical machining (ECM) is a method of removing metal by an electrochemical process. It is normally used for mass production and is used for working extremely hard materials or materials that are difficult to machine using conventional methods.[1] Its use is limited to electrically conductive materials. ECM can cut small or odd-shaped angles, intricate contours or cavities in hardened exotic metals, such as titanium aluminised, Inconel, Waspalloy, and high nickel, cobalt, and rhenium alloys. Both external and internal geometries can be machined.ECM is often characterized as "reverse electroplating," in that it removes material instead of adding it.
In the ECM process, a cathode (tool) is advanced into an anode (work piece). The pressurized electrolyte is injected at a set temperature to the area being cut. The feed rate is the same as the rate of "liquefaction" of the material. The gap between the tool and the work piece varies within 80-800 micrometers (.003 in. and .030 in.) As electrons cross the gap, material from the work piece is dissolved, as the tool forms the desired shape in the work piece. The electrolytic fluid carries away the metal hydroxide formed in the process.
Advantages and Disadvantages
Because the tool does not contact the work piece, its advantage over conventional machining is that there is no need to use expensive alloys to make the tool tougher than the work piece. There is less tool wear in ECM, and less heat and stress are produced in processing that could damage the part. Fewer passes are typically needed, and the tool can be repeatedly used. Disadvantages are the high tooling costs of ECM, and that up to 40,000 amps of current must be applied to the work piece. The saline (or Acidic) electrolyte also poses the risk of corrosion to tool, work piece and equipment.
EDM
Electric discharge machining (EDM), sometimes colloquially also referred to as spark machining, spark eroding, burning, die