Carbide is significantly harder, more wear-resistant, and retains its edge at higher temperatures, making it the stronger material for cutting and machining. However, cobalt is much tougher and more flexible.
No, carbide is significantly harder than cobalt.
Carbide drill bits are harder and more durable than cobalt bits, making them ideal for masonry and stone, while cobalt bits excel at drilling through stainless steel and can be resharpened multiple times. The choice between these two depends on your specific project needs and budget.
Carbide (specifically tungsten carbide) is the strongest and hardest standard drill bit material, offering unparalleled wear and heat resistance. However, because it is extremely hard, it is also brittle and prone to snapping if flexed.
A broken cobalt bit is pretty close to the end of the game, unfortunately. You can dig it out with a tungsten carbide and a mag drill, maybe. You aren't going to get it with a hand drill. Look for spade drills if you want to try anyway.
This guide will explore the various drill bits and what they are made of and list the top seven strongest options.
For the toughest jobs, we recommend carbide drill bits. These bits use tungsten carbide, an incredibly hard material that can cut through hardened steel with ease. While more expensive, they last much longer than other options.
Cobalt drill bits are some of the strongest options for tough materials like stainless steel. They're highly durable and heat-resistant due to their blend of cobalt and high-speed steel.
Cobalt is significantly stronger, harder, and more heat-resistant than titanium drill bits.
Tungsten carbide is stronger than steel, and the chemical makeup of the material makes glass drill bits extremely durable and long lasting. Glass drill bits are also sometimes suitable for drilling into tile, making them more versatile than you'd expect.
Their Drilling Applications Are Limited
The hardness of the cobalt alloy, which proves advantageous for tough metals, can lead to over-penetration and undesirable outcomes when used on softer materials. For example, these bits may cause wood, plastics, or other soft materials to split during drilling.
At 82 HRC, give or take, tungsten carbide is much harder than cobalt or HSS. This is carbide's only Achilles' heel—where cobalt will flex a fair amount in the face of radial cutting forces, carbide will in many cases shatter.
The price of tungsten carbide largely depends on whether you are buying finished stock or selling scrap. New, commercial-grade tungsten carbide stock typically costs between $30 and $50+ per pound, while scrap tungsten carbide is currently being bought by metal recyclers for $24 to $29 per pound.
The scrap value of carbide typically ranges from $𝟖 to $𝟐𝟗 per pound, depending on the exact material, the form (e.g., solid versus powder), and current market conditions.
Tough and Reliable Cobalt drill bits are well-known for their ability to handle high temperatures and wear, making them perfect for drilling through hardened steel.
Tungsten is ideal for certain high-wear and very high-temperature applications due to its hardness and high melting point, but it is also denser and significantly more expensive than stainless steel.
Different types of drill bits are also made of materials that enhance performance and durability. High-speed steel (HSS) works for wood, light metals and PVC. Cobalt is ideal for hard metals and stainless steel. Carbide-tipped bits excel in concrete, tile and masonry.
While titanium is indeed lighter and offers excellent corrosion resistance compared to steel, its high cost and complex manufacturing process make it impractical for most applications. Steel remains the preferred choice due to its versatility, cost-effectiveness, and established manufacturing processes.
Cobalt drill bits are extremely durable, particularly when drilling through tough, abrasive materials. They can withstand more stress and last longer than both black oxide and titanium bits in heavy-duty applications. Pros: Best for heavy-duty and tough drilling, great for hard metals.
Whether carbide is "better" than cobalt depends entirely on your setup. Neither is universally superior. Carbide is much harder and holds an edge longer, making it ideal for precision and high-speed CNC work. Cobalt is more flexible and heat-resistant, making it superior for handheld drilling and tough, vibrating jobs.
Cons
If you drill holes through both steel and stainless steel with standard drill bits, it is recommended that you use cutting oil or an appropriate liquid lubricant because the two metals react differently to heat.
Always drill metal on a slow speed combined with firm, steady pressure. High speeds generate excessive friction and heat, which will instantly burn and dull your drill bit.
For thick steel, the best choice is a Cobalt (M35 or M42) drill bit. Made of high-speed steel alloyed with 5% to 8% cobalt, these bits are highly heat-resistant, incredibly tough, and can be resharpened. Avoid standard black oxide or titanium-coated bits, as they will quickly burn out and dull in thick steel.