Machining Paper Base Phenolic Materials: What You Need to Know About Grades

May 22, 2019 | Materials, News, Paper Phenolic, Phenolic Machining

Paper phenolic material is a practically ubiquitous part of the world around us – even if a lot of people don’t realize it. It’s often used to make the types of substrates found in printed circuit boards, but it’s also very common in everything from punch parts to spacers to sleeves, panel boards and just about everything in between.

Generally speaking, there are three main grades of paper phenolic to concern yourself with: X, XX and XXX. While they may seem similar, it’s also critical to understand that they are not as closely related as they might appear. There are a number of important differences present that you need to be aware of so that you can make the most informed decision possible about which type of material to go with.

Grades X, XX and XXX: What’s the Difference? Breaking Things Down

Regardless of whether you’re talking about Grade X, XX or XXX, you’re still talking about a type of material that is made up of a mix between a phenolic resin and paper. As an aside, they also happen to be the material with the lowest coating in the entire phenolic category. They all have excellent mechanical properties and they’re all considered to be easy to machine, have excellent wear resistance, are known for their low moisture absorption and more.

Where the grades themselves start to matter a great deal, however, is when the discussion starts to extend into the realm of dielectric strengths. Each “X” in the grade essentially designates a different “level,” with each one becoming stronger and sturdier than the last.

  • Grade X paper phenolic, for example, is generally not recommended for situations where A) electrical properties are extremely important, and B) humidity is high.
  • Grade XX, on the other hand, has proven itself to be more than suitable for applications like electric insulation.
  • Grade XXX is not only a terrific option for its electrical insulating strength, but it also does very well in humid temperatures. Those gains will come with a sacrifice, however, that take the form of mechanical properties that are generally considered to be weaker than the other two options.

So based on exactly what it is that you’re trying to do, you’re therefore in the best position to pick the type of material you really need.

In terms of Military Specifications, you should also know that Grade X conforms to MIL-I-24768/12. Grade XX conforms to MIL-I-24768/11, while Grade XXX conforms to MIL-I-24768/10. This, too, will likely influence which paper phenolic you should pick for any particular job.

In the End

So while Grades X, XX and XXX all have properties like high impact and compressive strength along with a strong and stiff makeup, there are a number of important differences between them when it comes  down to the “nitty gritty” details. This is why it’s always so important to carefully consider your application first before you choose any type of paper phenolic material. They’re all excellent options, but depending on your desired outcomes they’re not all created equally.

This is also another situation where finding the right partner can come in handy – a company like JMJ Profile can help make sure that you’re always choosing the right type of paper phenolic material so that you can worry less about what might happen and focus on what will happen in terms of results.

If you’d like to find out more information about the machining of paper-based phenolic materials, or if you have any additional questions that you’d like to discuss with someone in a bit more detail, please don’t hesitate to contact JMJ Profile today.

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