The performance of chipped stainless steel materials in stainless steel machining services is poor. In the actual cutting of chips, there are mainly the following problems:
- For the problem of work hardening, work hardening is mainly manifested in the following three aspects: First, due to the greater plasticity of stainless steel materials and strong deformation, when deformation occurs, the lattice Produce a larger strengthening factor. The second is the cutting problem. During cutting, austenite becomes martensite due to stability problems, and the hardness of martensite is too high. The third is that it will be affected by temperature when chopped. It has been hardened, and this hardening phenomenon has an impact on the work of subsequent processes.
- Large cutting force is required, because the plastic will deform when cutting stainless steel material, and it is likely to harden during the chipping process, resulting in a large cutting force, so the chip tool needs to make a reasonable choice.
- The cutting temperature is high, because stainless steel has a strong plasticity, it will deform it, the friction between the workpiece and the tool will increase, and the heat of the chip will continue to increase. When the temperature is too high, work hardening will occur.
- The chips are easy to stick because the stainless steel has strong toughness. After the chips are processed, the wood chips are not easy to discharge, and it is easy to block the sawdust groove, which will increase the wear of the cutter, and even cause the teeth to break or the blade to break.
As long as it involves cutting, it must involve the setting and selection of saw blades and sawing parameters. The choice of sawing line speed is a very important indicator in the metal machining process. The line speed limits the service life of the tool. Important determinants. In the sawing industry, the most common problem is sawing of stainless steel. When machining stainless steel, a lower linear speed should be used. For example, in 201 and 202 materials, the line speed should not be higher than 30 meters per minute. However, the pipe cutters of many manufacturers on the market are too fast to be suitable for sawing stainless steel. This is a problem that many practitioners can easily ignore. When cutting stainless steel, the cutting line speed that high-speed steel saw blades can withstand is certainly not ideal. The selection of tooth profile angle γ (chip angle) is adjusted from 12° to 15° (usually 12°), and α (chip removal angle) is usually adjusted from 6° to 8°
Selection of feed speed The feed speed needs to be calculated by the corresponding calculation. The feed of each tooth of the saw stainless steel should be less than the feed of ordinary carbon steel. The feed of each tooth should be 0.02mm/Z~0.04mm/ Z (This is an empirical value. According to the specific situation of sawing, the coating of the blade is used as a reference. If the blade has a high-quality coating, this value can be taken within this range)
The role of the cutting fluid when sawing stainless steel, the part where the workpiece and the blade contact will generate a high temperature, which will make the blade wear and heat faster. In order to reduce the chip temperature, you can choose to add cutting fluid. Because the cutting fluid can absorb a lot of heat, it can reduce the errors caused by the temperature change of the workpiece, and can improve the chip life and the efficiency of the saw blade. Certain processes can neither use water cooling nor lubricating oil. Although a cooler is used, the effect of the cooler is definitely not as good as the cutting fluid.