Why is wire erosion (EDM) best for hard metals?

At Brindley Metals we focus on offering the most comprehensive service for our clients. To start we have access to a huge array of metal products, including plate, bars, sheets, and even specialist foils. We carry a massive range of metals and alloys, from steel to titanium. Then, we can arrange processing to suit many projects. This can even include wire erosion (EDM) for precision cutting.

One of the biggest issues with metal cutting is dealing with the hardness. Hard metals can be very challenging to cut. Traditional methods such as using hand tools may not be able to do the job effectively. Even modern options like CNC lathes may struggle, especially if they don’t have the right tooling.

Luckily, wire erosion (EDM) can usually handle the project. It is a great choice if you are working with hard metals that would damage other types of tooling.

Why is it such a good option?

The thing to keep in mind here is that EDM has exceptional cutting power but without high cutting forces. As a result, it can cut without exerting a great deal of stress on the metal. That is better for the workpiece and the tooling. Crucially it will mean there is often very little change in the mechanical properties of the metal.

The process involves the use of a wire, typically made of brass. It runs continuously from a spool and feeds between two guides. The spools can be incredibly long, sometimes over a dozen kilometres. That allows the wire to continue feeding to allow cutting through thick metals.

Wire erosion also has a big advantage in that workpieces are submerged in a tank of fluid. This provides a number of benefits. Firstly, it helps to cool the workpiece to prevent any damage from excessive heat building up. On top of this, it efficiently flushes away debris from the cut. This further reduces the risk of heat building up and improves the finish of the cut.

Even more impressively, EDM can be used to cut complex shapes from very hard metals. This is possible if the machinery allows the movement of the upper guide. If it can move independently on three axes it can allow things like tapering and intricate cutting.

Think about overcutting

One thing to keep in mind here though is overcutting. The way the EDM works, sparks will emit from the side of the wire. As a result, the actual cut will be wider than the wire itself. It may only be a few mils, but that can make all the difference with projects that require precision.

Luckily, it is usually relatively easy to make allowances for the overcut. Depending on the application, you should be able to get an idea of the actual size of the cut you can achieve with different widths of wire. You can therefore plan for it and compensate.

Talk to us about wire erosion (EDM)

Brindley Metals appreciates just how important it is to get accurate cutting services, especially with complex parts. We can arrange them with one of our partners, giving clients access to a wealth of experience and the best equipment. Whether it is cutting hard metals to make dies, punches, tools, or small components, or services for plate or bar, we can help.

So, if you need an efficient service, you can rely on us. Get in touch if you have any questions about using wire erosion (EDM) for particular grades or alloys of different metals. We can advise you and ensure you choose a solution to get the results you want.

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