The difference between normal wear and abnormal wear of cemented carbide tools
In recent years, industrial productivity has become more and more extensive, and it has become more and more widely used in the sub-sectors. However, in the process of production, there is little understanding of the scope of application, which will cause various problems and affect the production delivery cycle; for example, in normal life work, there will be The master of machining will ask, "Why can I use this blade for a little bit of time? I can't use it."
Carbide tools are subject to chip friction during the high temperature conditions, which will cause the tool to be worn and damaged, but how to distinguish between normal wear and abnormal wear?
Normal wear refers to a form of wear that gradually increases in wear over time, two of which are clearly expressed as normal wear.
The front wears and the crater wear occurs in the front edge of the blade, which is formed by friction and high temperature and high pressure when the chips flow out.
After the main wear, the main rear wear is divided into three areas, the blade wear is expected to be in the C zone. The wear loss VC is due to the low strength and temperature concentration at the near tip, and the intermediate wear B zone, except for the uniform wear amount VB. The maximum wear amount at the point of severe wear is VBmax, which is caused by the difference in friction and heat dissipation. The boundary wears N zone, and the wear of the cutting edge and the surface to be machined is VN, which is caused by the high temperature oxidation and the surface hardening layer.
Abnormal wear is usually caused by damage to the tool during impact cutting, uneven heating, and improper use of the carbide tool. The following types are abnormal wear of the tool.
The chipping occurs with fine chipping on the cutting edge due to the low strength of the cutting edge, the impact and the hard spots in the cutting layer.
Crushing, cracking at the tip or cutting point, the tool material is brittle, the cutting edge or cutting strength is low, and the cutting load is large, and the middle cut or cut is easy to occur.
Hot cracking, small cracks appear in the vertical cutting edge, due to uneven cutting temperature, discontinuous cutting, uneven casting of cutting fluid.
Collapse, under the action of high temperature and high pressure during cutting, the cutting edge loses cloud cutting performance and causes the front or the cutting edge and the cutting edge to collapse. This is when the cutting temperature of the high speed steel tool exceeds 650 degrees and the cutting temperature of the carbide cutting tool exceeds 1000 degrees. The form of damage that occurs.