High-strength nuts are also called screw caps, which are used to fix together with anchor bolts or screws. All manufacturing and manufacturing machinery requires the use of a component. There are many kinds of nuts, which are generally divided into national standards, German standards, international British standards, American standards, and Japanese standards. According to different materials, nuts are divided into carbon steel, high toughness, stainless steel, plastic steel and other important types. According to product characteristics, they correspond to different national standard serial numbers, divided into general, non-standard, (old) national standard, new national standard, American system, British system and German standard. For different sizes, threads are divided into different sizes. The so-called magnetic induction heating is the heating state of the product workpiece caused by the magnetic effect of the current when using the vortex formed by the product workpiece. Compared with traditional heat treatment, magnetic induction surface heat treatment has the following advantages: 1. Because the heat source is generated on the surface of the product workpiece, the heating efficiency is high and the speed is faster. Second, this type of nut does not require overall heating, so it is not prone to significant deformation. 3. Because it can be heated in a short period of time, the amount of oxidative carburization on the surface is relatively small. 4. The high-strength nuts of this type of technology have high impact toughness and wear resistance because of their high surface strength. It is healthy to develop the development potential of raw materials, save raw material consumption, and improve the service life of parts. 5. This kind of processing technology works well, has a high level of mechanical automation and intelligence, and is very convenient to use. High-strength nuts Under the effects of alternating loads and impact loads (such as twisting and bending), some parts experience higher stresses than the core. In the case of friction, the surface layer is also often damaged. Therefore, the requirements of high toughness, high hardness, high wear resistance and high fatigue strength are mentioned for the surface layer of some parts. The above requirements can only be achieved with surface structural reinforcement. Because of the advantages of small deformation and high production efficiency, surface heat treatment is widely used in production.