1. Early wear stage
Cutting machine tool early wear process is faster, shorter time. A new blade grinding tool surface peak more prominent, in the process of friction with the chip, the pressure is not uniform, the peak point of the pressure is larger, resulting in the peak is quickly worn, so that the pressure tends to even, wear speed slowed down.
2. Normal wear stage
After the early wear of the cutting tool surface, the peak point is ground, the pressure on the surface tends to be even, and the wear amount of the tool VB increases uniformly with the extension of time. The wear curve at this stage is basically linear, and its slope represents wear strength, which is an important index to compare tool performance.
3. Rapid wear stage
After the normal wear of the cutting tool, the cutting edge has become blunt, the cutting force and cutting temperature have increased sharply, the reason of wear has changed, the surface fatigue of the tool, the performance has decreased, the wear amount OF VB has increased dramatically, the tool will soon fail.
Cutting machine tool blunt standard:
Tool wear to a certain limit can not continue to use. This wear limit is called the cutting machine tool blunt standard.
Cutting machine tool life:
The actual cutting time experienced by a new (or re-sharpened) knife from the beginning of use until it has reached the grinding standard is called the tool life of the cutting machine.