Life prolonging method for quickly repairing microcracks of pump parts and life prolonging device for quickly repairing microcracks of pump parts

Abstract

A life prolonging method for quickly repairing microcracks of pump parts and a life prolonging device for quickly repairing the microcracks of the pump parts relate to the technical fields of metal surface protection and laser machining and application. The microcracks of pumps, particularly the microcracks of centrifugal pump shells are strengthened in a cold shock manner by the aid of power effects of laser shock waves; and coatings sprayed by the aid of the power effects of the laser shock waves contain 10-60% iron-titanium compound powder or flake zinc powder. Heating cracks are avoided during repair, the microcracks can be effectively repaired, the mechanical properties of the pump parts can be improved, and the problem of difficulty in practically applying the pump parts in acid and alkali liquid environments is solved. After the method and the device are used for repairing the damaged pump parts, the purposes of life prolonging and improvement of reliability and safety of the pump parts are achieved.

Description

technology field; [0001] The invention relates to the technical field of metal surface protection and the technical field of laser processing application, in particular to a method and device for quickly repairing and prolonging the life of micro-cracks of pump parts in an acid-base environment. Background technique [0002] Laser shock peening (LSP) is a technology that uses laser shock waves to modify the surface of materials to improve the properties of materials such as fatigue resistance, wear and stress corrosion. The principle is that the shock wave induced by high-energy short-pulse laser interacts with the material, forming a plastic deformation layer on the surface of the metal material, producing twin crystals and other crystals and forming a very small dislocation substructure, so that a large residual compressive stress is formed on the surface of the material , so that the fatigue strength, hardness and other properties of metal materials can be improved, espec...

AI Technical Summary

Problems solved by technology

Argon arc welding, plasma spraying, plasma arc welding, and tungsten inert gas shielded welding methods have a large amount of heat input during the repair process, and thermal cracks are prone to appear in the heat-affected zone, welding is easy to deform, and it is easy to fall off and crack during use. At the same time, the shrinkage deformation caused by the repair process makes it difficult to guarantee the installation accuracy of the blades, so the application of these methods has great limitations

Laser cladding is a process of ultra-fast heating and ultra-rapid cooling. It has the advantages of less heat input to the substrate, small heat-affected zone, fine cladding layer structure, good metallurgical bonding with the substrate, and easy automation. Compared with other methods, the laser cladding method has obvious advantages in repairing cracks in pump casings and blades, but internal defects such as cracks are prone to occur during the laser cladding process, which affects the quality of the cladding layer.

All of the above methods have a common disadvantage that cracks are prone to occur during the repair process, and the continuous expansion of cracks seriously affects the normal operation and service life of the pump casing and blades.

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