Preparation process of TiCN multilayer composite coating layer on slotting cutter surface of steam turbine rotor

Abstract

The invention relates to a preparation process of a TiCN multilayer composite coating layer on a slotting cutter surface of a steam turbine rotor; and the preparation process comprises surface pretreatment of a cutter basal body, cleaning, cutter clamping and loading, preparation of the multilayer composite coating layer, cooling and discharge, and aftertreatment. The multilayer structure formed by the coating layer preparation process uses TiN and TiCN as alternating coating layers to prepare 50 TiN and TiCN alternating coating layers on the slotting cutter surface; TiN is the backing layer; and TiCN is the outermost layer. The coating layer prepared by the method relieves the residual stress of the coating layer and the cutter basal body, so that the bonding force of the basal body and the coating layer is larger, the bonding degree of the coating layer is higher, and the coating layer is not easy to be stripped off. In addition, C atoms are introduced based on TiN to cause the lattice distortion and the solid solution strengthening effect, so that the surface hardness of the cutter basal body can reach HV3500, the cutter wear resistance is improved, the cutter service life is prolonged, the machining quality of the steam turbine rotor is guaranteed, and the production cost is reduced.

Description

technical field [0001] The invention relates to a metal processing tool coating, in particular to a preparation process for a TiCN multi-layer composite coating on the surface of a fir tree-shaped milling cutter used for processing steam turbine rotor wheel grooves. The multi-layer composite coating adopts TiN and Alternate coating forms of TiCN. Background technique [0002] The rotor is one of the most difficult, longest and most expensive core components in the production of steam turbines. Its fir tree-shaped wheel groove has complex shape and high dimensional accuracy, and the rotor is currently commonly used as a new material 26NiCrMov145, which has good toughness but poor thermal conductivity. , The work hardening is serious, so when machining the rotor fir tree groove, the cutting heat is large, the chip removal is poor, the cutting temperature is high, the groove tool wear is serious, the tool life is low, and the rotor processing efficiency and quality are affected...

AI Technical Summary

Problems solved by technology

This process provides a set of strict pre-treatment and post-treatment solutions for coated tools. The pre-treatment effectively improves the bonding force between the coating and the tool substrate, and solves technical problems such as easy peeling of the coating. The post-treatment removes droplets on the coating surface, etc. The process can effectively improve the processing accuracy and surface processing quality, so that the surface of the groove milling cutter has higher hardness, wear resistance and high temperature stability

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