HSS cobalt drill bit is probably not too unfamiliar to everyone, for some people, it may still be very familiar. Since ancient times, there have been people who have survived by engaging in this industry.
High-speed steel, also known as wind steel or front steel, means that it can be hardened even if it is cooled in the air during quenching, and it is very sharp. It is complex alloy steel, containing carbide-forming elements such as tungsten, molybdenum, chromium, vanadium, and cobalt. The total amount of alloying elements is about 10-25%. It can maintain high hardness even when high heat is generated by high-speed cutting (about 500℃), and the HRC can be above 60. This is the most important characteristic of high-speed steel-red hardness.
After quenching and low-temperature tempering, carbon tool steel has high hardness at room temperature, but when the temperature is higher than 200℃, the hardness drops sharply, and the hardness at 500℃ has dropped to a similar degree to the annealed state. , Completely lost the ability to cut metal, which limits the use of carbon tool steel to make cutting tools. High-speed steel, because of its good red hardness, makes up for the fatal shortcomings of carbon tool steel and can be used to make cutting tools.
Therefore, the hardness of the HSS cobalt drill bit is slightly higher than that of the wood auger drill bit , and the places used are also different.