As we all know, the wear of cemented carbide tools is serious, which will cause difficulty in heavy grinding and affect the machining quality of precision parts. Due to the different workpiece materials and cutting materials, the normal wear and tear of tungsten carbide tools has the following three situations:
1.Flank wear
Rear knife wear only occurs on the flank face. After wearing, it forms a facet that forms αo ≤0o, and its height VB indicates the amount of wear, which generally occurs when cutting brittle metals or plastic metals at lower cutting speeds and smaller cutting thicknesses (αc < 0.1mm). At this time, the mechanical friction on the rake face is small, and the temperature is low, so the wear on the rake face is large.
2.Crater wear
Rake face wear refers to the wear area that occurs mainly on the rake face. Generally, at higher cutting speed and larger cutting thickness (αc > 0.5mm) when cutting plastic metals, chips flow out from the rake face, and due to friction, high temperature and high pressure, a crescent crater is ground on the rake face near the cutting edge. The amount of wear on the rake face is expressed in terms of crater depth KT. During the machining of precision parts, the crescent crater gradually deepens and widens, and expands in the direction of the cutting edge, even leading to chipping.
3.The rake and flank faces are worn at the same time
The rake and flank faces are worn at the same time refers to the simultaneous wear of rake and flank faces on carbide tools after cutting. This is a form of wear that is more common when cutting plastic metals at medium cutting speeds and feeds.
The total cutting time of the tungsten carbide tool from the beginning of grinding to the processing of precision parts until the wear amount reaches the wear limit is called the carbide tool life, that is, the sum of the pure cutting time between the two regrinding of the carbide tool, which is indicated by "T". If the wear limits are the same, the longer the life of the carbide tool, the slower the wear of the carbide tool.
Post time: Jan-24-2024