Stainless steel is difficult to process mainly due to the poor thermal conductivity of stainless steel, and the heating of the chip material will easily form a buildup on the tip of the tool, which is the main cause of damage to the blade. In addition, because of the large cutting force and high cutting temperature during processing, brings some difficulties to the processing, and it is often difficult to achieve satisfactory results when cutting.
We learned from an engineer who has been in business for 40 years that there are also some tips for stainless steel processing. Let’s share the 304 Stainless Steel Cutting Tips today!
304 Stainless Steel Cutting Tips
1. The blade Angle of the cutting tool must be 0, and it can be ground on a tool grinder if possible. This is the most important point. Because when 304 stainless steel is cut, the chips and the groove wall friction are serious. If the chips cannot be rolled out vertically, chip squeezing will occur, and the knife will be hit in severe cases. When the blade inclination angle is large, the effect of chip splitting measures is not ideal.
2. The arc radius of the tooltip should not be too large, the auxiliary rear Angle of the tool is easy to wear when it is too large, it may be because the chip thickness at the arc is reduced, which is easy to produce hardening and aggravate the wear of the tool side.
3. Tool wear should be sharpened in time. The grinding standard of 304 stainless steel cutting knife, not only should be determined according to the main rear but also pay special attention to the degree of wear on the auxiliary rear. If the auxiliary back is worn too much, the friction between the tool and the groove side will increase, causing the groove width to narrow, making it difficult to discharge the chips, and accelerating tool wear.
4. The front surface roughness of the tool should be reduced as much as possible, the surface roughness value is low, which can reduce bonding wear and the cutting force, and cutting lightly. The practice has proved that the tool front after grinding than without grinding tool life significantly improved.
5. The cutting edge is ground with a negative chamfer of about 0.2mm, which can reduce the chipping phenomenon during grinding and obtain a better cutting edge quality. The lower part of the knife body adopts a fish belly shape to increase rigidity. The clearance angle of the tool pair is externally ground with a grinding wheel, and the rigidity is better. The actual clearance angle is about 2°～3°. The tool material for processing 304 stainless steel is generally selected from YG alloy which is not easy to bond and wear with it. I chose YG8 with better strength. The tool width is selected according to the diameter of the bar. The cutting speed is about 60m/min. This tool can meet the needs of general processing. The bar material of φ40～φ80MM can be cut at one time. There is no need to drive the knife around. Pay attention to the sharp stainless steel chips during processing. If the chips are too long, the knife must be retracted to break the chips. To avoid danger, the tool should not stay on the surface of the workpiece when retracting, to reduce work hardening. When cutting a solid workpiece, in order to avoid the tool from breaking, when cutting to the center, you can leave about 1~2mm to break it by hand.
6. For this kind of stainless steel cnc milling, under normal circumstances, wet cutting is several times longer than dry cutting tool life. The mainly is speed and cutting knife. If the speed is high without adding water, the chips from the cutting knife will be red immediately. It will be clear after processing a few activities!