The most direct and effective way to reduce machining costs is to effectively apply different parts of a turning tool. Therefore, in order to select the most suitable cutting tools, in addition to the selection of suitable cutting materials, it is necessary to understand the characteristics of cutting geometry. However, because of the wide range of cutting geometry involved, the focus is now on the application of the front Angle, the back Angle, which is most commonly used, and the effect of both on the cutting process.
Generally speaking, the front Angle has a great influence on cutting force, chip discharge and tool durability.
Front Angle influence
1) large front Angle and sharp cutting edge;
2) for every 1 degree increase of front Angle, cutting power decreases 1%;
3) the forward Angle is too large, and the blade strength drops; If the negative front Angle is too large, the cutting force increases.
Big negative front Angle
1) cutting hard materials;
2) large cutting edge strength is required to adapt to intermittent cutting and processing conditions of cutting surface with black skin.
Large front Angle is used
1) cutting soft materials;
2) free cutting materials;
3) when the rigidity of the processed material and machine tool is poor.
Benefits of using front - Angle cutting
1) the cutting efficiency can be improved as the front Angle can reduce the resistance encountered in cutting.
2) reduce the temperature and vibration generated during cutting and improve the cutting accuracy;
3) reduce the tool loss and prolong the tool life;
4) when choosing the correct tool material and cutting Angle, the front Angle can reduce the tool wear and enhance the reliability of the blade.
The front Angle is too large
1) the increase of the front Angle will reduce the Angle and cutting efficiency of the cutting part. Therefore, if the front Angle is too large, the cutting tool will be prone to wear and even collapse.
2) when the tool material is weak, the cutting edge reliability is hard to maintain.
After the Angle
The back Angle reduces friction between the tool and the workpiece, which makes the knife have the function of freely cutting the workpiece.
Influence of back Angle
1) the back Angle is large, and the back blade is wearing less
2) large back Angle and decreased blade tip strength.
Small back Angle
1) cutting hardness materials;
2) when cutting intensity is high.
Greater back Angle
1) cutting soft materials
2) easy working and hardening material for cutting.
Benefits of back Angle cutting
1) large back Angle cutting can reduce the wear on the back edge. Therefore, in the case of no sharp increase in front Angle loss, using large back Angle and small back Angle can extend the life of the cutter.
2) in general, it is easier to dissolve when cutting ductility and softer materials. Dissolving will increase the Angle and contact surface of workpiece, increase cutting resistance and reduce cutting precision. This situation can be avoided by cutting such materials at a large back Angle.
Limit of post - Angle cutting
1) when cutting materials with low heat transfer, such as titanium alloy and stainless steel, the use of large back Angle cutting will make the front surface of the cutter prone to wear or even damage. Therefore, large back Angle is not suitable for cutting this type of material;
2) although the use of large back Angle can reduce the wear on the back surface, it can accelerate the decline of the blade. Therefore, the cutting depth of cutting will decrease accordingly, affecting the cutting precision. For this reason, technicians need to adjust the Angle of the cutter periodically to maintain the precision of cutting.
3) when cutting materials with high hardness, such as large back Angle, the resistance encountered during cutting will lead to the defect or damage of front Angle due to the strong compression force.