For quite some time, people have been using Electro Discharge Machining (EDM), which is also referred to as Spark erosion to successfully erode materials from hard to machine location as well as shapes. Toolmakers encounter surfaces and shapes which are difficult to machine, and this is what lead to the introduction of spark erosion because with this technique one can machine surfaces and shapes which are very difficult when using traditional cutting tools. This knowledge has been in use for almost two decades. EDM machines are embedded with current generators.
Currently, EDM machines are computerized and are controlled numerically. With such machines, it is very easy to come up with a single set up meant to cut a variety of cavities.
What is Spark erosion machining?
Spark erosion machining is a technique applied when machining challenging pieces which are difficult to remove. This process involves the connection of the tool and the workpiece to a direct current; this generates a continuous spark between them.
The part where the spark comes in touch with the workpiece surface is heated to extreme temperatures. The molten metal on the workpiece surface evaporates, leaving a minute hole. Constant discharge results in several craters, continuously weakening the workpiece to the required finish.
The electrode and the workpiece are separated by a vacuum which is filled with an insulating fluid. The liquid makes it easy for the removal of the debris from the working part. The synthetic fluid is applied to regulate the temperature involved in this process, absence of this fluid would result in a thermal shock, by regulating the heat involved in this process then no temperature changes can occur.
The process is ideal when it comes to the manufacturing of intricate parts and can be utilized for the refurbishing of the used parts.
Spark and Wire Erosion
Spark and wire erosion are distinct Electrical Discharge Machining (EDM) methods which we use daily.
Electrical discharge machining can be defined as a machining method whose working principles can be applied for hard metals and those which are hard to machine through the use of ancient methods. EDM is only compatible with materials which are good conductors of electricity. Electrical Discharge Machining is built to get rid of intricate depressions neglecting the need for heat treatment in softening and re-hardening of the steel. This method is applied to various kinds of metals and alloys like Titanium, Super Duplex, etc.
EDM machines operate even under tight tolerances.
Pros of EDM involving machining:
-Intricate procedures which would be impossible to machine with ancient tools
-Severe tolerances when it comes to the world hardest materials
-Ensures the workpiece is very tiny in comparison to ancient cutting tools which can destroy a workpiece as a result of excessive pressure
-The tool and the workpiece have no close contact. This makes it possible for sections susceptible to breakages and soft materials to be machined without causing any form of distortion.
-Proper surface finish is obtained easily
-Suitable holes can be drilled easily
