Drill with a flashlight, higher hardness, steel selection, material bit good?
When the material hardness of Rockwell hardness more than HRC30, such as heat treated steel, then only use the hard alloy drill bit, because of the hard alloy drill bit redhardness other material can not match the hard alloy bit refers to the hard alloy bit only embedded in the cutting part.
When the material hardness exceeds Rockwell hardness HRC20, such as spring steel, stainless steel and so on, can use cobalt cobalt high speed tool steel drill bit drilling, its heat resistance than ordinary high-speed steel bit has greatly improved.
General use of high-speed steel tool steel drill, only suitable for drilling in the Rockwell hardness HRC20 the following materials, such as the common Q235 plate, this is our common bit, can still keep good hardness cutting it at 600 degrees Celsius temperature.
