Drilling through hard material can be a difficult task for the drill bit. It would help if you had the right tool to do this. While we often hear that solid carbide drill bits are a better solution for hardened steel, others believe that cobalt drilling bits are also irreplaceable for drilling stainless steel. To find the right drill bit for you, let’s look at our comparison between cobalt and carbide drill bits.
The main difference between carbide and cobalt drills is their different materials. Carbide drill bits are made from tungsten carbide, while cobalt drill bits are made from high-speed steel with cobalt mixed into the alloy.
Cobalt drill bits are primarily made from high-speed steel with 5–8% cobalt added. This combination improves the heat and wear resistance of the drill bit, making it durable.
Tungsten carbide is a composite material produced by powder metallurgy and composed of refractory metal compounds (hard phase) and bonding metals (bonding phase).
Tungsten carbide is approximately twice as hard as steel, with a Young’s modulus of around 530–700 GPa, and is double the density of steel. It is one of the most rigid materials, only second to diamond.
Carbide bits are harder than cobalt bits. They also tend to last longer and retain their shape better. They are also more costly. You can sharpen carbide drill bits with special tools or diamond grinding wheels. They are not recommended for hand drilling as they can easily lose their shape. Carbide drill bits are generally ten times more expensive than cobalt bits.
Cobalt drill bits are low in melting point so they won’t burn your hands. They are also suitable for drilling cast iron and steel. They can wear down if they are overused or used for high-speed drilling. You’ll need them to be sharpened regularly.
Carbide drill bits are more durable than cobalt bits and can withstand higher heat.
Cobalt bits are less expensive than carbide drill bits. Cobalt bits are also self-centering, which makes them ideal for precision drilling. These drill bits are used for drilling non-ferrous material and in industrial applications.
It is crucial to choose the right drill bit for your job. It is crucial that the drill bit matches the material, the diameter, and the volume of the work. The right choice will increase productivity and extend the life of your drill bit.
Cobalt drill bits
Cobalt drill bits are used for general applications that don’t require high hardness drilling.They work well on hardwood, plywood, plastic, and metals such as aluminum, stainless steel, and other ferrous metals.
Carbide drill bits
Carbide drill bits are with the best performance on the market right now. They are perfect for high precision and long tool life when cutting hardened and tough materials. Conversely, this is the material of choice when cobalt drill bits aren’t up to the task.
Carbide-cutting tools are used on CNC machines for precision and high-volume production. However, in applications that don’t require extremely high cutting volumes, the cobalt drill bits will be more cost-effective since they much much cheaper.
Conclusion: Cobalt vs. Carbide Drill Bits
Cobalt and carbide drill bits are good choices for high performance drill bits. Carbide drill bits are more expensive than cobalt drill bits and with more performance. Also, they both support self-centering and suitable for precision drilling.
Carbide drill bits are the hardest and best choice for long tool life and abilities to drill hardened steel along with other difficult-to-machine materials. However, they are very expensive so they are normally used in high-volume industrial applications involving high-precision and mass production.
Cobalt drill bits are better for lower-volume work since they are much cheaper yet also provide good performance for woodworking, metalworking, and fabrication. If you are a hobbyist to do DIY at home or using hand drills or manual drill press for your work, then these bits are more cost-effective choice.