Engineering topics
Publications and source records attributed to Puchkin, V. N..
A dynamic system is analyzed by the simulation of two subsystems (for the part and the tool) that interact through the dynamic link formed by the machining process. This link corresponds to the smoothing forces, which may be expressed in terms of the state of the dynamic system. The dynamic stability and behavior of the system are expressed in terms of displacements from equilibrium.
Flake formation (cracking) is observed in inserts of untreated cutting ceramic and also during diffusional strengthening of the inserts’ surface layer by nitrogen on heating in a muffle furnace to 450–500°C, with the creation of γ-phase (a protective layer), the removal of carbon from the atomic cells, and the formation of titanium nitride. Heat-treatment conditions for inserts of cutting ceramic are established such that the flake content at their surface is reduced. Treatment to prevent flake formation is proposed: heating in a sealed muffle furnace with a nitrogen atmosphere to 250–280°C at a pressure of 0.25 MPa. In this process, the titanium carbide at the surface of the inserts is converted to titanium nitride as a result of carbon diffusion, with the formation of a protective γ-phase layer. By removing carbon from the surface layer of the inserts and ensuring the diffusion of nitrogen into the cutting ceramic, with the formation of titanium nitride in the γphase, the durability and performance of the inserts are improved, along with their mechanical properties.