As superalloy is a kind of material with high hardness and high temperature resistance, it is difficult to ensure the cutting accuracy when cutting with optical fiber laser cutting machine. What are the difficulties in processing superalloy with optical fiber laser cutting machine compared with ordinary steel?
1. Poor thermal conductivity of the superalloy: a large amount of heat generated when cutting the superalloy is borne by the oxidation end, and the cutting end bears a cutting temperature of up to 600~800 ℃. Under the action of high temperature and laser cutting, deformation, adhesion and diffusion wear will occur at the cut end, which will affect the processing quality of the workpiece;
2. The working surface is easy to harden: for example, the hardness of the GH4169 superalloy substrate before the non strengthening treatment is about HRC37. After the optical fiber laser cutting machine cuts, the surface will produce a hardening layer of about 0.03mm, the hardness will increase to about HRC47, and the hardening degree will be as high as 27%. The surface hardening caused by the working has a great impact on the life of the oxidation end, usually causing serious boundary wear;
3. The cutting force required is large: the strength of superalloy is more than 30% higher than that of common alloy steel materials. At the cutting temperature above 600 ℃, the strength of nickel base superalloy materials is still higher than that of common alloy steel materials. The unit cutting force of unreinforced superalloy materials is more than 4000N/mm2, while that of common alloy steel materials is only 2500N/mm2.
The above are the difficulties of optical fiber laser cutting machine cutting superalloys, and also the technical problems that need to be solved urgently in the current industry. I believe that in the near future, this problem will be effectively solved, promoting the development of the entire laser cutting machine industry.