Archive: Jun 2022

How Micro-Tronics Leverages EDM Manufacturing for Unusual Alloys

How Micro-Tronics Leverages EDM Manufacturing for Unusual Alloys

Have you struggled to get machined parts made from unusual alloys such as inconel, tungsten, rhenium and molybdenum?

Precision machine shops tend to specialize in CNC machining, but some exotic materials require a different, non-contact manufacturing method: electronic discharge machining (EDM)

At Micro-Tronics, we specialize in both traditional CNC machining and EDM. So when customers bring us materials that are too hard, soft, or brittle for conventional machining, we have the option of getting the job done with our in-house EDM services. 

Unusual Alloys Pose Challenges to Conventional CNC Machining

While some materials like Inconel and titanium can be cut using traditional CNC machining, there are challenges to consider. Materials that are exceptionally hard—or even very soft—pose risks during precision machining that can add cost and time to a project. 

For example, when machining strong and rigid materials, operators must run conventional machines at reduced speeds to mitigate tool wear and breakage. This extra time, plus the anticipated wear on tooling, often contributes to increased costs. 

In other cases, certain unusual alloys tend to “bite,” creating the risk of the tool “walking” during precision machining and potentially throwing the part out of spec. Softer materials might “smear,” making it difficult to get a sharp, clean cut. 

The process of EDM manufacturing uses electrical current and an electrode to send said electrical current to the workpiece. In wire EDM, the wire electrode is continuously replenished, eliminating the problem of tooling wear. We can cut parts cleanly, ensuring exceptional accuracy (measured in microns) and a smooth surface finish without impacting costs and lead times. In sinker EDM, we can utilize multiple electrodes if needed to ensure top quality parts throughout a production run.

7 Unusual Alloys We Machine at Micro-Tronics 

Here are seven unusual alloys we cut at Micro-Tronics using either our in-house CNC machining or Wire EDM / Sinker EDM services:

1. Rhenium

Rhenium is an exceptionally dense material with good ductility and high strength.

Well-suited for high-temperature applications, it’s a popular choice for aerospace parts, such as exhaust nozzles, turbine blades, engine components, and combustion chambers. 

The only downside? Rhenium is very expensive.

2. Molybdenum

Known as “moly” in the industry, molybdenum is best known for its lubricity and often used as a lubricant additive. It provides a slick feel to surfaces—similar to graphite—without grease or oil. It also has an extremely high melting point.

Molybdenum is a common additive in alloys. It’s found in Teflon and “moly steel” alloys, which have increased hardness, strength, electrical conductivity, corrosion resistance, and wear resistance.

3. Inconel

From the nickel-chromium family, Inconel is resistant to corrosion and oxidation and capable of tolerating extreme environmental conditions. These characteristics make it a prime candidate for underwater applications such as propeller blades and submarine motors.

Additionally, Inconel’s ability to withstand high temperatures and maintain its strength when heated renders it an excellent match for aerospace applications.

4. Stainless steel

From industrial equipment to automotive parts to cooking tools, stainless steel is the second most common material manufactured in precision machine shops. It’s extremely durable and possesses high tensile strength and good corrosion resistance.

However, when hardened and heat-treated, stainless steel is nearly impossible to machine conventionally. Specialty grades of stainless steel pose a similar challenge. Austenitic steels (the family of stainless steels with high chromium content and nickel) are prone to work hardening, and alloys such as 303, 304, and 316 can experience material build-up.

5. Copper alloys

Copper alloys are commonly found in electrical components and medical parts. Boasting high electrical conductivity and corrosion resistance, these alloys also possess high ductility, and toughness, making them difficult to machine with a standard mill or lathe. 

Beryllium copper is often used for thermal transfer applications due to its ability to withstand high temperatures. However, once airborne, beryllium particulates can be toxic, so a certain degree of expertise is required to machine this material safely. Beryllium copper can also be abrasive to tooling, making it even more challenging to work with.

6. Titanium

Commonly found in aerospace applications, titanium alloys have high tensile strengths and superior toughness, even at extreme temperatures. They’re also relatively lightweight for their strength and highly corrosion resistant. 

However, the properties that make titanium so desirable make it a challenge to machine traditionally. The high tensile strength and low conductivity levels can result in broken tools and ruined parts.

7. Tungsten

Tungsten is one of the heaviest materials used in machining and has an exceptionally high melting point (3,410 degrees Celsius). 

It’s often used as an additive in other alloys or treated with carbides or hard metals to create a material with hardness comparable to a diamond. Common applications include aerospace parts, automobile components, electronic appliances, and products made for construction. 

Micro-Tronics Has the Experience to Machine Exotic Materials 

Machining Inconel, tungsten, molybdenum, and other exotic materials requires a breadth of knowledge about the different materials and optimal machining methods. These materials are typically expensive, so it’s important to work with a manufacturing partner who knows what they’re doing.

At Micro-Tronics, we have 50+ years of CNC machining and EDM manufacturing experience and confidently machine many unusual alloys for our customers. 

We’ll work with you to identify the best manufacturing process. We may even suggest both CNC machining and EDM services, in which case we can save you significant time and money by keeping your entire project under one roof. Request a quote to work with us!