CNC Machining Cast Iron: All You Need to Know

Machining cast iron is a process that is commonly observed in a lot of applications, however, it requires sufficient knowledge to ensure optimum results. If you are looking to learn about the process of CNC machining cast iron this guide below can be of great help. So let's read below.

What is CNC Machining Cast Iron?

The process of CNC machining iron comprises computer-controlled machines. These machines help to cut the cast iron in different shapes and designs as required for the cast iron components for different applications.

CNC machines use different tools that are made using carbide so that the abrasive nature of cast iron can be handled. The cast iron components manufactured using CNC machining offer complex geometries, high precision, and uniform quality.

Types of Cast Iron for CNC Machining

There are different types of cast iron that are commonly used in CNC machining and some of these types are as follows:

Gray Cast Iron

Gray cast iron is one of the most common types of cast iron which is used in applications like pipes, engine blocks, and different cookware items. It comprises graphite and this is what makes it gray. It offers good machinability, less brittleness, and high compressive strength.

Ductile Cast Iron

Ductile cast iron has nodules of graphite which add toughness and flexibility to the cast iron. The addition of graphite nodules makes the cast iron equipped with impact resistance and has high tensile strength. It is then widely used in the automobile industry, crankshafts, and gears.

Malleable Cast Iron

Malleable cast iron comes into being when white cast iron is treated with heat. The heat treatments allow for altering the molecules of carbon and it converts them into nodules with irregularity. This form of cast iron has toughness and ductility and it is less brittle. Malleable cast iron is used in agricultural machinery, pipe fittings, and different automobile parts.

White Cast Iron

White cast iron has a high content of carbon and has a white color with a shiny look. It comprises iron carbide which makes it highly absorbent and wear-resistant. Hence, it is commonly used in applications that are wear-intensive like grinding balls and mill liners.

Advantages of CNC Machining Cast Iron

CNC machining cast iron comes with ample benefits and some of these may comprise the following:

Suitable for Intricate Designs

Cast iron is a type of material that is highly suitable for manufacturing complex shapes that have intricate designs. Hence, it is used in components that require detailing through CNC machining.

High Machinability

Cast iron comprises graphite that acts as a natural lubricant and therefore when machining it, the process becomes very easy, but the graphite flakes in the gray cast iron especially make it highly machinable.

High Tensile Strength

Cast iron orders high tensile strength. They are capable of holding the compressive loads. Therefore custom cast iron parts manufactured through CNC machining are used in structures and buildings commonly.

Affordability

Cast iron is low cost when compared to cast aluminum or cast steel. Hence it offers a highly affordable option for most of the applications and is therefore chosen.

Finishing Options for CNC Machined Cast Iron Parts

After the process of machining cast iron parts need some surface finishing which helps to enhance the quality of the parts. Some of the available finishing options are as follows:

Bead Blasting

The sandblasting surface finishing process is one of the basic methods. It is usually used for parts that require little or no finishing.

The process involves blasting abrasive in the form of a high pressure stream on the part. It helps to remove rust and impurities from the part and improves the strength and durability of cast iron parts.

Powder Coating

Powder coating uses different colors of powder paint which is sprayed on the surface of components. It helps to have an attractive and durable finish. It offers thickness and uniform layers on the surface and is highly environmentally friendly. The components subjected to powder coating offer a high resistance against corrosion.

Painting

The process of painting is adding a layer of protection on the cast iron component. It is applied in the form of liquid and it enhances corrosion resistance and the appearance of components. It is usually selected for cast iron parts which are subjected to harsh conditions.

Electroplating

Electroplating is a process of surface finishing in which metal atoms are deposited on cast iron parts in the form of a thin layer. Usually, zinc plating is chosen for cast iron components offering it a reflective and shiny finish. It improves the hardness of the surface and is suitable for components in highly corrosive environments.

Tips for CNC Machining Cast Iron

When machining cast iron, some of the important tips to improve the process are given below:

• Choosing the right cutting tools is crucial to have precise and high-quality cuts and shapes. In this case, carbide tools are highly recommended for CNC machining.
• The cutting speed of cast iron must be adjusted based on the type of cast iron chosen, however, the feed rate should be moderate.
• During the process of machining cast iron, the use of coolant can be a concern because machining cast iron is a dry process. The use of coolant creates a slurry that may be difficult to clean from the component.
• Chip evacuation is very important when it comes to CNC machining cast iron as it produces fine abrasive chips during machining.

Applications of Cast Iron Machined Parts

There are multiple applications of custom cast iron parts and some of these are given below:

Automotive

Cast iron is used in the automobile industry as it has the capability to withstand high pressure and temperature. It is highly cost-effective for automobile components and is used in engine blocks, gears, cylinder heads, and brake rotors.

Cooking Utensils

There are a lot of cooking products that are made using cast iron. It doesn't leach any type of toxic chemicals which makes it safe for cooking. Also, cast iron has a surface that is non-stick and it can also be used on campfires and grills.

Construction

In the construction industry, the use of cast iron is popular. It has a high tensile strength and resists deformation. Therefore it is suitable for pipes and bridges and is also opted for pipe fittings.

Cooling and Heating Systems

Heat exchangers and radiators are manufactured using CNC-machined cast iron. It is opted for these applications due to the seamless heat diffusion properties it offers and its durability. The fireplace inserts and cast iron stoves are also popular for offering heating.

Outdoor Furniture

Outdoor furniture like garden statues, benches, and lamp posts are even manufactured using cast iron. It has the ability to offer intricate designs and the best part is that it resists harsh weather conditions very well.

Conclusion

Cast iron plays a vital role in multiple industries due to its seamless properties. It is affordable, durable, and resistant to wear and tear. If you are also looking for the cast iron parts manufactured for your application specifically you can contact DEK. We offer custom cast iron components through CNC machining ensuring their intricate layout and high quality.

FAQs

How are cast iron parts made?

The molten iron is poured into the molds and upon solidification, the desired cast iron part is achieved.

Precautions when machining cast iron?

When CNC machining cast iron, always wear a mask so that you don't inhale the cast iron particles.