High-speed laser spraying device adopting coaxial powder feeding

Abstract

The invention discloses a high-speed laser spraying device adopting coaxial powder feeding. The high-speed laser spraying device comprises a supporting seat; the supporting seat comprises an outer supporting seat body and an inner supporting seat body; a gap is formed between the outer supporting seat body and the inner supporting seat body, and the outer supporting seat body and the inner supporting seat body are connected through a plurality of supporting ribs; a spectroscopic reflector and a shrinkage and expansion type nozzle are mounted at the top and the bottom of the inner supporting seat body correspondingly, and a focusing reflector is mounted at the top of the outer supporting seat body; the spectroscopic reflector, the focusing reflector, the shrinkage and expansion type nozzleand the supporting seat are coaxial; and a gas powder channel communicating with the shrinkage and expansion type nozzle is formed in the supporting seat. A single-beam collimation laser emitted froman opening in the focusing reflector is directly emitted to the spectroscopic reflector of a regular pyramid structure to obtain a plurality of reflecting light beams to achieve beam splitting, the reflecting light beams are emitted to the focusing reflector to obtain a converged light beam, and the converged light beam is focused at an outlet of the shrinkage and expansion type nozzle to form focusing light spots coaxial with the shrinkage and expansion type nozzle; under the effect of compressed gas accelerating airflow, powder is ejected from the shrinkage and expansion type nozzle to jointhe focusing light spots; and by adopting coaxial powder feeding, the purpose of high-speed laser spraying capable of reducing powder splashing is achieved.

Description

technical field [0001] The invention relates to a laser spraying equipment, especially a coaxial powder feeding high-speed laser spraying device. Background technique [0002] The laser spraying process uses laser as a heat source to heat the powder material to a molten or semi-molten state, and at the same time accelerates the powder material with the help of the gas jet to spray and deposit it on the surface of the substrate at a certain speed to form a coating. This process is similar to plasma Compared with thermal spraying techniques such as spraying and high-speed flame spraying, the biggest difference is that this process uses laser as a heat source, and the process of powder heating is very fast. At the same time, the substrate deposition spot area is also heated by laser, while the gas can not be heated, and the energy utilization rate High, while plasma and high-velocity flame spraying usually use the high heat and high kinetic energy of the airflow to heat and acc...

AI Technical Summary

Problems solved by technology

The central beam mode usually has the following disadvantages: because the powder converges obliquely to the focal point of the spot and then disperses again, the interaction range with the laser is small, resulting in serious powder splashing and low utilization rate; the adjustable range of the laser spot is small, and the cladding head requires high precision

There are also some other unfavorable factors in the laser spraying of the central beam. For example, the Chinese invention patent application "A Multifunctional Coaxial Powder Feeding High-speed Laser Spraying Device and Its Application" with the application number 201710996639. In this way, the high-pressure gas is accelerated by the nozzle arranged in the center and then output coaxially with the laser beam. At the same time, the powder feeding tube and the conical powder feeding gap are arranged on the wall of the laser cavity tube and arranged at an acute angle with the axis of the laser cavity tube. Although it can realize Basic laser spraying, but because the central high-pressure gas jet is arranged separately from the powder, the acceleration distance of the high-pressure gas jet to the powder will be limited, and there is a defect of insufficient powder acceleration, which greatly limits the development space of the advantages of laser spraying technology

For the center powder feeding, the Chinese invention patent application with the application number 201711184987.7 has announced a central powder feeding expandable multi-beam laser cladding head and its application, through the multi-beam laser combination design of at least two laser output heads to realize the center powder feeding , that is, multiple laser output heads are arranged circumferentially on the top of the main frame with the powder feeding tube as the center, and are combined in space inside the cladding head to complete the intersection with the central powder feeding channel. This design requires the use of multiple laser beams. If the number of beams is too small, it is not conducive to the uniform distribution of energy, it is not coaxial in the true sense, and this design puts forward higher requirements for the laser and transmission optical path, which increases the complexity and cost of the equipment to a certain extent

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