How do you tell which materials are used in the test?
Cutting different materials depends more on the shape of the cutting edge. Different cutting edges are used for different materials. Experience is very important. Take a look at the schematic diagram of the drill edges.
The commonly used twist drills are the hardness HRC62~68 of high speed steel (W18Cr4V or W9Cr4V2) after quenching.
The drill shall be selected according to the material properties of the material to be machined. For example, stainless steel uses cobalt cobalt drills. Use tungsten cobalt alloy bit when producing high heat when the bit is cutting
