Target knife utilizing laser surface texture optimization

[0016] The present invention will be further described below with reference to the drawings and embodiments.

[0017] Such as figure 1 As shown, a targeted knife using laser surface texture optimization includes a stainless steel targeted blade body 1. The surface of the targeted blade body has an optimized surface tissue layer 2 through laser phase change hardening or laser remelting, so that the surface of the blade is extremely The thin hardened tissue improves the wear resistance and high temperature oxidation resistance of the blade surface, reduces the friction between the blade and the human tissue, improves the freezing and ablation effects, thereby reducing the knife edge and reducing the pain of the patient.

[0018] Laser phase change hardening is widely used in the field of material surface modification because of its high power density, high surface strengthening quality, small impact on the original during processing, local processing on complex originals, easy automatic control and no pollution. . Laser transformation hardening is also called laser quenching. High-energy density laser beams are used to irradiate the blade part that needs to be hardened to rapidly heat up the area to form austenite, and then rapidly cool to obtain a fine martensite and other hardened layers of structure. The surface hardness of the blade treated by phase change hardening is high, and a very fine hardened structure can be obtained, so the wear resistance is improved. At the same time, due to the high speed of laser processing, the heat affected area is small and the surface finish is high.

[0019] Laser remelting is to use a laser beam to melt the surface without adding any metal elements, which can achieve the purpose of improving the surface structure. Using laser to remelt the surface of the blade can release impurities, pores, and compounds, and at the same time, the crystal grains can be refined due to rapid cooling. Compared with the laser quenching process, the key of laser remelting treatment is to make the surface of the material undergo a rapid melting-solidification process. Its main features are: generally no alloying elements are added when the surface is melted, and the fusion layer and the material matrix are natural metallurgical bonding; during the laser fusion process, impurities and gases can be removed, and the structure obtained by quenching recrystallization at the same time, so there is High hardness, wear resistance and corrosion resistance; its melting layer is thin, the heat action area is small, it has little effect on the surface roughness and the original size, and it can even be used directly. Because the laser remelting surface heat treatment technology can improve the high hardness, wear resistance and corrosion resistance of the tool surface, it has a good application prospect in machinery, chemical and medical equipment industries. After laser remelting, the surface microhardness of the tool is greatly improved, and the corrosion resistance, wear resistance and high temperature oxidation resistance are also better.

[0020] The specific method of laser transformation hardening: irradiate a regular strong laser beam to the surface of the target knife, and quickly increase the surface temperature of the target knife to above the austenite transformation temperature and below the melting point. Through the rapid movement of the laser beam, the target knife The heated part quickly exchanges heat with the inside, and the cooling rate of the target knife surface is extremely fast, thereby completing the martensite transformation and obtaining extremely fine martensite.

[0021] Similarly, the specific method of laser remelting is to use higher power density (10~10W/cm 2 ) Laser beam scans the stainless steel surface of the target knife to melt the stainless steel on the surface, and then rapidly cool and solidify.

[0022] Such as figure 2 As shown, due to the very fast heating and cooling rate of laser remelting, the primary phase during solidification is the austenite phase. In this process, the higher cooling rate weakens the redistribution of the solute, making the primary austenite phase too late A transformation occurs, causing the ferrite to disappear.

[0023] In summary, the laser phase change hardening and laser remelting of the stainless steel surface of the blade can optimize the surface structure without changing the composition. The wear resistance of the surface of the blade is reduced, and its corrosion resistance and high temperature oxidation resistance are also improved, which can improve the freezing and ablation effects to a certain extent, and at the same time reduce the blade edge and reduce the pain of the patient.