What's the difference between wood hole drill, metal hole drill and stainless steel hole drill?

The spring plays a buffering role, and the inclined hole plays a cutting role.

Quarter point, isn't it Brad's sharp drill? If there is, it is used to drill wood (the general drill bit is carbon steel S45C). High-speed steel should be used as the drill bit for drilling iron. (High-speed steel bit)

Stainless steel bit belongs to high speed steel bit. Because of the high tensile property and dense grain structure of stainless steel (just like a tightly held hand), it needs to be wear-resistant and high-temperature resistant when opening the sheet. In the process of drilling stainless steel, it is necessary to resist high temperature and wear. M35 cobalt-containing bit is generally selected. In IRWIN and DEWALT brands, engineers designed Turbomax (polit point) drill tips to drill stainless steel. This drill tip design is characterized by fast positioning, fast cutting and small wear of the drill tip. In order to reduce the production cost, many factories use M2 cobalt-free materials to drill stainless steel.