Method and device for light, powder and gas coaxial transmission laser cladding forming manufacturing

Abstract

The invention discloses a method for light, powder and gas co-axial transmission laser cladding forming manufacturing, which is characterized in that: a circular section solid laser beam emitted by a laser is subjected to transformation and beam expansion by the optical path transformation to become a circular laser beam; the circular laser beam is focused to become a hollow circular cone focused laser beam; a powder spraying nozzle is arranged on the hollow part of the circular cone focused laser beam; the powder spraying nozzle and the circular cone focused laser beam are coaxial; the periphery of a single powder beam sprayed by the powder spraying nozzle is provided with a circle of collimation shielding gas curtain; and the collimation shielding gas curtain, the circular cone focused laser beam and the single powder beam sprayed by the powder spraying nozzle are coaxial. By arranging the collimation shielding gas curtain on the periphery of the powder beam, the method realizes the coaxial transmission of light, powders and gas and solves the defects in the prior art.

Description

technical field [0001] The invention relates to the field of laser processing and forming, in particular to a method and device for coaxially conveying light, powder and gas to produce laser cladding and forming. Background technique [0002] In the prior art, the simultaneous powder feeding laser cladding forming of metal materials is completed by a special laser cladding nozzle, the method and structure of which are disclosed in European Patent WO2005028151 and Japanese Patent JP2005219060. The basic principle is that the beam is centered and the metal powder is surrounded and conveyed: the cylindrical laser beam emitted by the laser is focused into a solid conical laser beam, the processing surface is placed near the focus, and multiple relative beam axes are arranged around the solid conical laser beam With the inclined powder spraying nozzle, the converging point of the multiple powder beams ejected from the multiple powder spraying nozzles is just placed near the focal...

AI Technical Summary

Problems solved by technology

However, there is a big deficiency in the existing scheme. The trajectory of the powder is a converging-diverging paraboloid. When the powder beam is sprayed out of the powder tube, the powder loses the constraint of the tube wall, and the motion parameters of the powder particles with different particle sizes and shapes will fluctuate. The movement trajectory and landing point of the powder particles in the air will also be inconsistent, which will result in a large range of powder particle drop areas, difficult to stabilize the convergence accuracy, poor rigidity of the powder beam, and easy divergence

The shielding gas 1 sprayed from the middle of the powder diffuses the powder beam outward, while the shielding gas 5 diffuses the powder beam inward, so there is a problem of pressure coordination between the double-layer shielding gas, its size adjustment control is very sensitive, and it is difficult to accurately converge the powder beam

Due to the unstable amount of powder entering the molten pool, the powder sprayed next to the molten pool is not melted or not penetrated after the molten pool solidifies, causing physical and geometric defects on the formed surface

Cladding practice has proved that the airflow formed by the double-layer shielding gas near the nozzle is generally turbulent, and the powder splashes around during processing, the powder utilization rate is extremely low, and the environmental pollution is great

[0004] In view of the above-mentioned deficiencies, the applicant once disclosed in Chinese patent CN200610116413.1 a laser processing and forming manufacturing optical internal powder feeding process and an optical internal powder feeding nozzle, which realized the hollow focused laser beam internal powder feeding and improved the coupling of light and powder. accuracy, but it does not involve the transmission method of the shielding gas, and the relationship between the shielding gas, the focused laser beam, and the powder beam; the powder still diverges after being sprayed out of the powder nozzle; the collimation and rigidity of the powder beam need to be determined. improve

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