How to Choose the Right Material for Your Cutting Tools

When it comes to carrying out various applications on a CNC machine or lathe, it can be confusing to understand what material tools you need. There is a variety of cutting tool materials available that all come in different grades. The grades and type of material are vital considerations before starting any metal cutting project. Other considerations that are needed to help you achieve a successful cut are the workpiece material to be machined, the component type and shape, machining conditions and the level of surface quality required for each project. It is important to understand that cutting tool materials all have various combinations or hardness, toughness and wear resistance, which divide them into different grades with specific properties.

Rennie Tool knows the importance of getting a high-quality cut for every project. We get that the choice of cutting tool material can be confusing and can make or break your project. That’s why we have created this guide on how to choose the right material for your cutting tools to help you find the best tools for the job. From carbide tools to steel cutting tools, you can understand what is best for certain projects and how each material works.

What a Cutting Tool Material Needs

The cutting process is tough and can wear down cutting tools easily. This is because they are under extreme conditions, such as high cutting pressures, severe friction and huge impact forces. Due to the tools operating in this environment, it is pivotal to select the best materials for the application you want to do. If you use the wrong material, you can quickly wear down the tool, which can lead to premature failure or even significant breakage.

So, what does a cutting tool material need to have to give you the best possible cut for all types of projects?

• High hardness: The material must maintain its hardness at high temperatures to resist deformation and wear.
• Toughness: It needs to be very tough to prevent chipping and fracture under impact loads.
• Wear resistance: Your cutting tool needs to withstand abrasive and adhesive wear mechanisms to give a long lifespan.
• Thermal shock resistance: The tool needs the ability to withstand rapid temperature changes without breaking or failing.
• Hardness in heat: It should remain at the level of hardness and strength it has usually when faced with high temperatures.
• Thermal conductivity: Having good thermal conductivity dissipates the heat from the edge of the cutting too. This reduces thermal stress to make the tool last longer.
• Resistant to chemicals: Needs to be resistant to chemical reactions with the workpiece material. This stops the quick degradation of the tool.
• Easy to fabricate: The material you use needs to allow forming, grinding and any other manufacturing process.

Which Material is Best for Your Cutting Tools?

So, which material will be best to use? Well, this is dependent on the type of project you’re carrying out, the material you’re cutting, and the machining conditions you need for a successful cut. Below are some of the more popular cutting tool materials that you will more likely need to use for all sorts of applications. This helps to put an end to the never-ending questions, like ‘what steel cutting tools can I use?’, making it easier for you to get straight to creating!

Tungsten Carbide

Tungsten carbide is a combination of tungsten metal with carbon atoms. It is a very hard substance that is commonly used in the manufacturing of tools and wear-resistant components. This cutting tool material has an extremely high melting point and, so, can resist high temperatures. The material is also very resistant to corrosion compared to other metals such as gold, silver or platinum, making it very durable.

The appearance of tungsten carbide is a solid, light grey metal that has a melting point of 3422°C with an outstanding corrosion resistance. It has a hardness of 7.5 on the Mohs scale and has the strength of hardened steel. This means that even though it is hard and durable, it is also soft enough to be cut with a hacksaw.

Because of its outstanding properties, this material can be the best cutting tool material for a wide array of projects. It is extremely versatile and sought-after in many industries. But what can you use it for?

• Construction projects
• Alloys
• Surgical instruments
• Jewellery.

Stainless Steel Drill Bits

If you’re working with stainless steel, then you will want to use stainless steel drill bits. These aren’t necessarily bits made from stainless steel but are various drill bits that are best to use for stainless steel material. Since stainless steel is a tough metal, you will need something equally as hard and resistant to wear to give you a precise cut.

There are three length dimensions, which are short, long and extra-long. The short length is sturdy and doesn’t easily break, while the extra-long is the flying length. This means it has high drilling and cutting precision. Bit sizes also play into the quality of the cut. Large diameter ones are sturdy and stable for stainless steel, while smaller diameters can break.

Stainless steel is typically very popular to use in the automotive industry but is used in a variety of other industries for many applications. However, because various materials fall under stainless steel drill bits, it can be confusing to understand what to use.

Cobalt and Titanium drill bits can be used for stainless steel, especially with step drill bits. These are resistant to overheating, so they are perfect for projects needing high temperatures.

Black oxide drill bits are durable, and the oxide makes them stronger than ordinary HSS drill bits. These have a powerful cutting strength for stainless steel and are very robust.

Tungsten carbide bits have a high heat resistance, strong cutting ability and are strong like a diamond. They are the perfect choice of tool for drilling stainless steel at extreme temperatures.

HSCO bits are cobalt-coated drill bits that are exceptional for cutting metals. They have a hardness like no other, perfect for tough applications.

High Speed Steel

High-Speed Steel (HSS) is a high-alloy tool steel that contains more alloy elements like tungsten, chromium and vanadium. It can withstand cutting temperatures of 550-600°C and reaches a cutting speed of 25-30m/min. It is ideal for cutting general steel at a rapid rate. It also has incredible strength and toughness, as well as a good amount of hardness and wear resistance. This makes its bending strength 2-3 times that of cemented carbide.

Due to the high-speed steel material properties, it is perfect for a wide range of projects and can be used for processing on machines with poor rigidity. This material is easy to sharpen, and the cutting edge can be forged. This makes it useful for manufacturing tools with complex shapes. It can be used for complex tools, like drills, taps, forming tools, broaches and gear tools.

Carbide Tools

Carbide tools are very durable, and they don’t react with elements of nature. They have a high wear resistance and can be ideal for high-speed functions for long periods of time. This cutting tool material has immense strength and hardness that can help in a lot of different projects. They can withstand harsh environments without breakages or failures. The tools are made by combining tungsten carbide with a metallic binder, which creates a material that is tough enough to handle the most challenging machining applications.

They can be used for milling operations to remove material quickly and efficiently, while giving a smooth and accurate finish. You can also use it for drilling to create holes in many materials, and, due to their resistance to high temperatures and speeds, they are perfect for high-speed drilling applications. They can even be used for turning. It can remove material from the surface while the workpiece is rotating and is great for high-volume production as they can withstand high temperatures and speeds.

PCD Tooling

PCD tooling stands for Polycrystalline Diamond and is a man-made composite material. It fuses together small, synthetic diamond particles with a metallic binder. This gives this material unparalleled strength with high-pressure and high-temperature tolerances. The diamonds provide the cutting edges and are what make this tooling incredibly hard and resistant to wear. It gives a precise cut for projects needing precision and excellence. The material can be put through extreme environments and pressure, while withstanding gradual damage and erosion during the cutting process. This means if you have a time-consuming, harsh project, PCD tooling is the best to use. It also ensures that workpieces don’t get damaged and has the potential to work at higher speeds.

It can be used for composite materials, nonferrous materials, wood products and hard plastics. You can carry out milling, turning, drilling, grinding and sawing with this material and it is best for intricately detailed projects. It’s typically used for the automotive industry for machining alloys in engines, transmissions, and wheels. However, it can also be used in aerospace for lightweight airframe structures, woodworking and furniture, electronics, construction and flooring and energy for fiberglass components.