A high-strength and high-wear-resistant composite braze coating for repairing turbine blades

Abstract

The invention relates to a high-strength and high-wear-resisting composite braze coating for repairing water turbine blades, which is made by mixing low-melting-point brazing filler metal and high-melting-point cemented carbide with a weight percentage of (1-9):1, and then coating and heating , the low-melting-point solder is a mixture of any two or three of iron-based solder, copper-based solder, and nickel-based solder, and the high-melting-point hard alloy is a mixture of carbide and boride. The high-strength and high-wear-resistance composite brazing coating provided by the present invention is an organic mixture of iron-based, copper-based, nickel-based low-melting point brazing materials and carbide, boride, and diamond high-melting point hardening materials, which have high strength, high hardness, high wear resistance, Unique advantages such as high corrosion resistance, among which the wear resistance is 37.2-51.9% higher than that of the substrate, the corrosion resistance of the composite brazing coating is increased by 2-3.5 orders of magnitude, and the bonding strength between the coating and the substrate is increased by 0.56-1.18 times, which can effectively solve the problem. Pores, corrosion, cracks, wear and other defects of hydraulic machinery in overcurrent and sediment environments.

Description

technical field [0001] The invention relates to the technical field of repair coating on the surface of water turbine blades, in particular to a high-strength and high-wear-resistant composite brazing coating used for repairing water turbine blades. Background technique [0002] Due to the wear and cavitation of the river and sediment for a long time, the turbine blades will produce fatigue cracks and sediment corrosion defects, which need to be repaired regularly (about one year) on site to improve the working efficiency of the turbine. The repair of turbine blades often adopts methods such as surfacing, cladding, and arc welding. However, due to the lack of professional repairing methods for blade repairing and welding at present, only traditional methods are used to repair surface defects, which has low work efficiency and low bonding strength, which is not in line with the reality of energy saving, emission reduction and green environmental protection in modern manufactu...

AI Technical Summary

Problems solved by technology

[0004] A Chinese patent has been published: an automatic surfacing device for repairing guide vanes of hydraulic turbines (201811650242.X), which improves welding efficiency and solves the problems of high labor intensity for manual surfacing repairs and difficulty in ensuring surfacing quality

A method for repairing cracks in hydraulic turbine blades (201510549734.X), using X-detection and laser beam methods to repair blade cracks, but the process is relatively complicated

The on-line laser strengthening device for turbine blades (201910205181.4) overcomes the problems of large heat-affected zone of base materials, low bonding strength, difficult control of thickness, unenvironmental protection, large operating space, and low repair efficiency during the traditional arc welding defect repair process of turbine blades.

However, the above-mentioned blade repair device lacks the monitoring of the profile information of the repair layer and the interlayer temperature, and the thickness of the repair layer cannot be accurately controlled, and the goal of real-time optimization of process parameters cannot be achieved.

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