1. Abrasive Wear and Tear
Principle: In the process of iron cutting, the sawtooth of the saw blade rubs against the surface of the steel material, and the hard points in the steel material, such as carbide and oxide, will scrape and cut the surface of the sawtooth like abrasive grains, resulting in the gradual shedding of the surface material of the sawtooth and the formation of abrasive wear. This wear is more noticeable at the beginning of the saw blade cutting, and gradually increases with the increase of cutting time. For example, when cutting alloy steel with a high carbon content, due to the high carbide hardness in the steel, it will produce strong abrasive wear on the saw blade serrations, causing obvious scratches and micro-cutting marks on the surface of the sawtooth.
Influencing factors: The hardness and impurity content of steel materials, as well as the hardness and wear resistance of saw blades are the main factors affecting abrasive wear. The higher the hardness of the steel material and the more impurities, the stronger the abrasive wear effect on the saw blade. The higher the hardness and wear resistance of the saw blade, the stronger the ability to resist abrasive wear. In addition, processing parameters such as cutting speed and feed can also affect the degree of abrasive wear. Higher cutting speeds and feeds increase friction between the blade and the steel material, which accelerates abrasive wear.
2. Adhesion Wear
Principle: During the cutting process, the saw blade serration is in close contact with the surface of the steel material at high temperature and high pressure, so that the atoms on the surface of the two are diffused with each other to form an adhesion point. As the blade continues to move, these sticking points are torn, causing the material on the sawblade's serrated surface to be carried away, creating adhesive wear. Adhesive wear usually occurs at higher cutting speeds and higher cutting temperatures. For example, when cutting stainless steel at high speed, due to the large viscosity of stainless steel, it is easy to adhere to the saw blade serration, and as the cutting progresses, the adhesive point is constantly formed and torn, so that the surface of the saw blade serration appears sticky chips and peeling.
Influencing factors: Cutting temperature, pressure, and the affinity of the saw blade to the steel material are key factors affecting adhesive wear. The higher the cutting temperature, the faster the atoms diffuse and the more likely it is that adhesive wear will occur. Excessive pressure also increases the probability of adhesive point formation. In addition, the closer the chemical composition of the saw blade material to the steel material, the stronger the affinity, and the more severe the adhesive wear. For example, when using ordinary high-speed steel saw blades to cut aluminum alloys, due to the high affinity between high-speed steel and aluminum alloys, it is easy to suffer from adhesive wear, while the use of tungsten carbide saw blades is significantly reduced due to its low affinity with aluminum alloys.
3. Fatigue and Wear
Principle: During the iron cutting process, the saw blade teeth are subjected to periodic mechanical and thermal loads. With the increase of the number of cuts, fatigue cracks gradually occur in the material on the serrated surface under the action of alternating stress. These cracks continue to expand, connect, and eventually cause the material on the serrated surface to peel off, resulting in fatigue wear. Fatigue wear usually occurs after a period of use of the saw blade, which is one of the important factors affecting the service life of the saw blade. For example, in cutting operations with frequent starts and stops, the saw blade teeth are subject to greater impact loads, which are more prone to fatigue wear. The saw blade used in this condition for a long time will cause many fine fatigue cracks on the surface of the sawtooth, and the sawtooth will break in severe cases.
Influencing factors: The size and frequency of the cutting load and the fatigue strength of the saw blade material are the main factors affecting fatigue wear. The greater the cutting load and the higher the frequency, the greater the alternating stress on the saw blade teeth and the more likely fatigue wear will occur. The higher the fatigue strength of the saw blade material, the greater the resistance to fatigue wear. In addition, the manufacturing process of the saw blade, such as heat treatment process, surface treatment process, etc., will also have an impact on the fatigue strength of the saw blade. For example, a saw blade that has undergone proper heat treatment has a more uniform internal structure and improved fatigue strength, which can effectively delay the occurrence of fatigue wear.
4. Corrosion and Wear
Principle: In the cutting process, when the saw blade is in contact with the steel material, due to the high temperature generated by friction and the action of the medium in the surrounding environment (such as the chemical composition in the cutting fluid, oxygen and moisture in the air, etc.), the surface of the saw blade will react chemically and form corrosion products. These corrosion products are gradually removed during the friction between the saw blade and the steel material, resulting in the loss of material on the sawtooth surface of the saw blade and corrosive wear. Corrosive wear is evident in humid environments or when cutting fluids containing corrosive components are used. For example, when cutting with cutting fluids containing additives such as sulfur and chlorine, the chemical components in the cutting fluid may react chemically with the saw blade material, accelerating the corrosion and wear of the saw blade.
Influencing factors: The corrosiveness of the environmental medium, the composition of the cutting fluid and the corrosion resistance of the saw blade material are important factors affecting corrosion and wear. The more corrosive the ambient medium, the more corrosive the wear of the saw blade. The type and content of additives in cutting fluid will affect its corrosiveness, and choosing the right cutting fluid can effectively reduce corrosive wear. The corrosion resistance of the saw blade material depends on its chemical composition and structure, for example, the saw blade material containing chromium, nickel and other alloying elements has good corrosion resistance and can resist corrosion and wear to a certain extent.