Choice of tools

Tools
YG cemented carbide has good toughness and thermal conductivity, and it is not easy to bond with chips. Therefore, it is suitable for stainless steel rough machining. The hardness, wear resistance, heat resistance, oxidation resistance, and toughness of YW cemented carbide Better, suitable for precision machining of stainless steel.
When processing 1Cr18Ni9Ti austenitic stainless steel, It is not suitable to use YT cemented carbide. because the Ti in stainless steel and Ti in YT cemented carbide have a pro-combination effect. Stainless steel shavings easily take away the Ti in the alloy and promote the wear of the tool.
The choice of tool geometry angle has great influence on the yield of stainless steel cutting, the cost of tool resistance, the roughness of the surface to be machined, the cutting force and the work hardening. Selecting and improving the tool geometry angle is an effective way to ensure the quality of processing, efficiency, and cost reduction.

(1)The size of the tool rake angle γ0 determines the sharpness and strength of the cutting edge. Increasing the rake angle can reduce the chip deformation, thereby reducing the cutting force, lowering the cutting temperature, and improving the tool resistance cost. However, increasing the rake angle will reduce the wedge angle, reduce the blade edge strength, cause chipping, and reduce the tool resistance cost. When turning stainless steel, the rake angle should be appropriately increased without reducing the tool strength. When the tool front angle is large, its plastic deformation is small, the cutting force and cutting heat are reduced, the work hardening tendency is reduced, and the tool resistance is improved. Generally, the tool front angle should be 12° to 20°.
(2) Selection of the turning angle α0 of the turning tool During the cutting process, the back angle can reduce the friction between the flank surface and the cutting surface. If the relief angle is too large, the wedge angle will decrease, so that the heat dissipation condition will be worsened, the tool edge strength will decrease, and the tool resistance cost will be reduced. If the rear corner is too small and the friction is severe, it will make the cutting edge blunt, increase the cutting force, increase the cutting temperature, and aggravate the tool wear. Under normal circumstances, the back angle does not change much, but there must be a fair value, in order to help improve the tool's endurance. When turning stainless steel, because the elasticity and plasticity of stainless steel are larger than ordinary carbon steel, the small clearance angle of the tool will increase the contact area between the cutting surface and the back angle of turning tool, and the high temperature area produced by friction will be concentrated in the back angle of turning tool. To accelerate the wear of the turning tool and reduce the finish of the surface being machined. Therefore, the turning angle of the turning tool when turning stainless steel is slightly larger than that when turning ordinary carbon steel. However, if the back angle is too large, the strength of the cutting edge will be reduced, directly affecting the resistance cost of the turning tool. Therefore, in general, the lathe angle should be 6° to 10°.