What kind of tool wear will occur in the process of turning and milling
In turning milling compound machining, tool wear is often caused by one main reason and combined action. Under different processing conditions, the main factors that cause tool wear are different, mainly including the following:
1. Abrasive wear
In the cutting process, the chip, some smile hard spots with high hardness in the workpiece material, such as the first level chip buildup, can carve grooves of different depths on the tool surface. This is hard spot wear, also known as abrasive wear.
When high-speed steel end milling cutter is used for turning and milling process, because the hardness of high-speed steel cutter is not high compared with that of cemented carbide cutter, the cutting speed is low, and the heat resistance is poor, when the turning milling composite processing is not at high cutting temperature, abrasive wear becomes the most significant wear reason for high-speed steel cutter.
2. Diffusion wear
At high cutting temperature, the tool surface contacts with the workpiece and chip surface, and the chemical elements of the tool and workpiece diffuse to each other, changing the composition and structure of the original material, weakening the performance of the tool material, and accelerating the wear process. Diffusion wear mainly occurs in high-speed cutting, so the cutting temperature is very high and the element diffusion rate is high. At the same time, with the increase of cutting speed, the degree of diffusion wear increases.
3. Oxidation wear
Slight oxidation of tool surface is beneficial to reduce tool wear, because the existence of oxide film can avoid direct contact between tool chip and tool workpiece, thus reducing adhesion. However, when the cutting temperature is high, the oxidation of tool materials will be very intense, forming a series of soft oxides. These oxides are stolen by chips or workpieces, resulting in the loss of tool materials, which constitutes oxidation wear in turning milling composite processing