Ultimate Guide for Ceramic Machining

Machining is a popular fabrication technique in today’s production industry. You can make parts and components from different materials.

Today, we want to introduce you to the world of machining ceramic materials. Although machining ceramic can be difficult, this guide offers an ultimate solution.

Let’s dive right into the details of the ceramic machining process.

Can you Machine Ceramics?

Yes.

Ceramic machining refers to various processes that transform ceramic materials into useful products. You may use different techniques to fabricate ceramic materials during the machining process.

As you will see later in this guide, the process may include drilling, milling, or grinding. It will depend on the machined ceramic parts you wish to make.

With the right technique, you can make valuable ceramic parts for different industrial applications.

Advantages of CNC Ceramic Machining

Ceramic is a unique material known for very distinct properties such as:

• High hardness
• Electrical insulation
• Heat resistance
• Chemical stability

It is for this reason that fabricated ceramic parts are popular in many industries. From, aerospace, automotive, and electrical to the medical industries, machined ceramic parts guarantee unmatched performance.

The machining process for ceramic parts fabrication gives you the ability to produce intricate ceramic parts. This is quite practical when you adopt the CNC machining process.

Other advantages of fabricating ceramic material are mainly attributed to the benefits the materials offer. That is, the process is:

• Versatile since you can make many ceramic parts or components
• Compared to other fabrication techniques, machining can be cost-effective
• The entire process is scalable depending on the ceramic part demands

Common Challenges during Ceramic Machining Process

Unlike other materials such as metals or plastics, machining ceramic materials can be a difficult task without the right information.

Knowing the challenges associated with the process will help you mitigate possible problems that may affect ceramic part quality. Let’s look at some challenges you will experience when machining ceramic materials:

All these will affect the quality of the final ceramic components. With the advancement in technology, most fabricators are adopting ways to overcome the above challenges.

With that in mind, let’s explore some ways to improve the quality of machined ceramic parts.

Ways to Improve Quality when Machining Ceramic Material

There are many ways to improve part quality during ceramic fabrication.

Remember, these practices may vary depending on the ceramic machining technique. For instance, during the CNC fabrication process, it is critical to control machining ceramics speed and feeds. Of course, this may be different when drilling ceramic or milling ceramic.

Having said that, let’s look at other ways to improve the quality of machined ceramic parts:

Adopt Advanced Tooling Systems

For a successful machining process, you need tools that can overcome ceramic hardness. At the same time, the cutting tools should not wear easily. For this reason, ceramic fabrication companies are adopting:

• Tooling systems with diamond coating
• Ceramic-based cutting tools

Configuring Ceramic Fabrication Parameters

Certain fabrication parameters determine the surface finish quality, alongside other parameters such as heat build or tool wear.

Before you start fabricating ceramic, you must know:

• Cutting speed
• Material feed rate
• Depth of cut

All these will help prevent possible tool wear and damage to the ceramic material.

Use Coolant to Prevent Heat Buildup

Coolant will prevent heat buildup and offer lubrication during the machining process. This will ensure there is no thermal buildup hence high-quality ceramic parts.

Additionally, you must adopt various vibration-damping mechanisms. This will eliminate abnormal vibrations that may damage both tooling and ceramic parts.

Incorporate Post Machining Operations

Whichever machining operation you choose for fabricating ceramic material may not produce the best part. At times, ceramic material may have certain residual stress or irregular surfaces.

Therefore, you will adopt appropriate post-machining operations to reduce the impact of thermal stress. Additionally, surface finishes may improve aesthetics, thereby eliminating possible residual stress as well.

Know the Properties of Ceramic Material

It is critical to know the types of ceramic material you are machining. This will help you choose the right cooling fluid, tooling systems, and fabrication technique.

For instance, the melting point of ceramicsvaries depending on the material composition. With this knowledge, you will know the temperature limits beyond which you cannot fabricate ceramic material.

How to Machine Ceramic Materials

Fabricating or engineering ceramic materials depends on 5 main basic pillars. Ideally, they determine the process you can adopt to achieve a high-quality ceramic part.

So in this section, we will simply have an outline of what you can expect when processing ceramic material. Let’s get to it:

1. Technical Drawing and Ceramic Prototyping

Every ceramic fabrication process starts from a concept. The engineers will then convert the concept into a technical drawing.

From here, you can then evaluate whether making ceramic part is feasible or not. Once approved, then the ceramic prototyping can begin.

With the prototype parts, you will conduct the tests, calculate the cost, and check if the parts meet the necessary safety compliance. Next, you can begin the mass production process.

2. Selecting Ceramic Material for Fabrication

There are many examples of machinable ceramics. Remember, the material you choose will depend on specific application or industry requirements.

Remember, advanced ceramic machining requires the material to meet strict quality and safety standards. It does not matter whether you are starting:

• Zirconia ceramic machining
• Silicon nitride machining
• Alumina silicate ceramic machining
• Silicon carbide parts machining or any
• Machining sintered ceramics

Other machinable ceramic materials are boron nitride, steatite ceramic, quartz, cordierite ceramic, mullite ceramic, macor, graphite, and mycalex, just to mention a few.

Whichever material you choose, it is important to choose the right tooling system. For instance, machining alumina parts and silicon carbide parts may require different tooling sets or cooling systems.

Even with the brittle, poor thermal conductivity, and high hardness, you can choose the correct tooling. Of course, this is alongside machine processing parameters.

In short, be clear on the ceramic material you would like to machine.

3. Machine and Tool Selection

Since ceramic is naturally hard and brittle, you may require a special tooling system. This is even critical for precision ceramic machining or custom ceramic machining.

In most cases, ceramic fabrication uses diamond tooling systems or carbide tooling systems. Therefore, the ceramic machining tools must withstand the fabrication forces without possible damage.

Again, the ceramic fabrication machine will depend on the process you wish to undertake. The fabrication process may include ceramic drilling, ceramic grinding, ceramic milling, etc.

At the same time, you must choose a proper cooling mechanism to prevent possible damage to both ceramic material and tooling system.

4. Tolerance and Accuracy

The brittle nature and hardness of ceramic material may be a challenge when it comes to tolerance control. By choosing an appropriate tooling system, you can achieve tight dimensional tolerance.

Remember, certain applications such as those in the aerospace industry require very tight tolerances.

The truth isthat you can still achieve very tight tolerances in ceramic machining.

5. Surface Finish on Fabricated Ceramic Parts

Post-processing operations on fabricated ceramic parts may vary depending on intended applications. You may grind or polish fabricated ceramic parts.

But even with all these processes, dimensional accuracy is still vital.

In short, by integrating all these pillars, you can easily engineer practical ceramic parts. With a clear framework, machining ceramic materials is still practical and cost-effective.

Types of Ceramic Machining Techniques

Whether you are focusing on small-part or large-part machining, you will choose a technique that guarantees a high degree of precision and accuracy. In the recent past, CNC machines have become popular among many ceramic material fabrication companies.

Let’s look at some common ceramic machining processes:

Grinding Ceramic Material

In this technique, you will use an abrasive tooling system to remove particles from ceramic material. Depending on your machine type, you can grind ceramic using:

• Grinding wheels
• Grind belts

Even though grinding ceramics is a popular fabrication technique, always select suitable grinding parameters. It will prevent possible damage to the ceramic material. Remember, ceramic surface brittleness and hardness are some of the main challenges in ceramic grinding.

Electrical Discharge Machining Ceramic

Unlike grinding ceramic, electrical discharge machining (EMD) is a non-contact process. In this process, you will use electrical discharges to remove particles from ceramic material.

For successful electrical discharge machining on ceramic, you must configure these parameters:

• Machine discharge energy
• Dielectric fluid
• Electrode material

For many years, EMD ceramic has remained a popular technique for:

• Complex ceramic parts
• Intricate ceramic shapes

Furthermore, in electrical discharge machining ceramic, you don’t have to worry about the brittleness and hardness of ceramic material. EMD seamlessly machines ceramic without applying any force that can damage parts.

However, there are challenges you have to deal with:

• Slow machining process
• There are chances of having a recast layer on ceramic parts

Milling Ceramic

You can also mill ceramic material as long as you have the right tooling system. Remember ceramic is tough and brittle which can be a little problematic.

With a rotating cutting tool, you will remove material from ceramic thereby making complex shapes, parts, or slots.

Remember, milling ceramic is a versatile process. Therefore, depending on the shape or part complexity, you may adopt various techniques such as:

• Face milling
• End milling
• Peripheral milling

Whichever ceramic milling technique you choose, it is important to pay attention to the feedrate, tool geometry, and cutting speed. All these variables will affect the final ceramic part quality.

CNC Turning Ceramic

The most common machine for this ceramic fabrication technique is the machining center. By rotating ceramic material, you can make many cylindrical ceramic parts.

Like ceramic milling, when turning ceramic material you must pay attention to cutting speed, material feed rate, and geometry. Of course, you will need a specialized cutting tool to fabricate ceramic.

Drilling Ceramic

With an appropriate tooling system and equipment, you can create holes in ceramic materials. You will use specialized drilling tools that can handle hard and brittle ceramic materials.

As you drill ceramic material, you must pay attention to the:

• Drilling speed
• Types of lubricant
• Feed rate

Once you pay attention to these, you will create holes without damaging the ceramic material.

Apart from these, other machining operations for ceramics may include wafer dicing, honing, ultrasonic machining, lapping, laser beam cutting, and inner diameter slicing.

Examples of Ceramic Machined Parts

Many industries depend on ceramic parts made through various machining techniques. From military, aerospace, electronics medical to consumer industries, there are thousands of ceramic components.

Let’s summarize some of the most common applications and types of ceramic material in the table below:

Example of industries that benefit from ceramic materials include:

• Automotive industry – ceramic brake pads, gears, spark plugs, etc.
• Medical industry – orthopedic accessories, implants, etc.
• Aerospace industry – Nozzles, electronic insulators, bearings, etc.
• Electronics industry – Dielectric materials, vacuum interrupters, circuit boards, heat sink, etc.

Do you have any ceramic material you wish to machine for specific applications? Well, you can consult our team for accurate ceramic material analysis and recommendations on the applications.

FAQs

1. What is the Machinability of Ceramics?

Yes, you can machine ceramic using special tools and equipment to get the final part you may need.

2. Is Ceramic Processing the same as Ceramic Machining?

Well, ceramic processing is a broad term referring to various practices that may involve transforming material into a desired shape, or finished product. On the other hand, machining ceramic is a subset of ceramic processes.

However, ceramic machining only refers to using specialized tools and equipment to cut material sections thereby forming a final product.

3.  Why is Ceramic Difficult to Machine?

At times, ceramic may be difficult to machine due to its inherent properties. Remember, ceramic is:

• Naturally brittle
• Resistant to creep
• Hard

Therefore, ceramic may be difficult to machine with conventional tooling systems.

Conclusion

As you can see, machining ceramic material can be a challenging process without the right knowledge. You must know the ceramic material properties, choose the right tooling, and select appropriate process parameters.

At KDM, we will help you get custom ceramic parts depending on your technical drawing and specification – contact us now for inquiries.