A built-in sieve ring laser cladding nozzle

Abstract

Disclosed in the present invention is a built-in sieve-hole annular laser cladding nozzle, comprising a laser head connecting part, a middle sleeve part, and a nozzle part, the laser head connecting part comprising an upper connecting sleeve connected to the laser head, the middle sleeve part comprising a sliding sleeve connected to the upper connecting sleeve, protective glass being disposed between the lower end of the sliding sleeve and an upper end of a central sleeve, a water cooling sleeve of the protective glass having a threaded connection to the sliding sleeve and the central sleeve, and protective air holes being disposed on the central sleeve, the nozzle part comprising a conical nozzle core connected to the central sleeve, a powder inlet sleeve, an air intake sleeve, and a water cooling sleeve being disposed in turn on the outer side of the conical nozzle core and the central sleeve. The present invention overcomes the defects of existing laser cladding nozzles, including the short service life, being unable to adjust the powder concentration diameter, and being unable to adapt to powder particles of different sizes.

Description

technical field [0001] The invention relates to the technical field of laser processing, in particular to an annular coaxial laser cladding nozzle. Background technique [0002] Laser cladding technology is a new surface modification technology, which is a process method that fuses two or more materials with different properties by heating to give full play to their excellent properties. Laser cladding has the characteristics of fast heating speed and cooling speed, and the obtained cladding layer has a fine microstructure, high strength, and performance is obviously superior to other cladding methods, so it has been widely concerned by material workers from all over the world. [0003] The powder feeding nozzle design of laser cladding is a key technology in laser processing equipment. The function of the powder feeding nozzle is to transform the powder flow from the powder feeder into different shapes and enter the laser beam to control the injection angle and cross-secti...

AI Technical Summary

Problems solved by technology

In-depth research on coaxial powder feeding nozzles has been carried out at home and abroad, and certain results have been achieved, but there are still many deficiencies, as follows: (1) In the absence of protective gas, the outlet of the powder feeding pipe is easy Clogging, which tends to cause the powder to flow out of the laser beam before reaching the substrate surface, forming areas where the cladding material is non-metallurgically bonded to the substrate

(2) The amount of powder feeding is uneven

During the implementation of the coaxial powder feeding laser cladding process, the flow of the cladding material in the laser beam is divergent, causing the powder spot diameter to exceed the laser spot diameter, and the powder beyond the laser spot diameter range is not fully heated in the laser beam. It will cause the cladding powder and the substrate surface to fail to form a metallurgical bond, which will directly lead to the deterioration of the surface of the formed part, and even lead to collapse in severe cases, making the forming process unable to continue

(3) The powder feeding nozzle cannot realize the precise coaxiality adjustment of the powder and the laser beam, resulting in powder spots and laser beams not being able to achieve coaxial work

(4) The laser beam will reflect on the surface of the substrate, resulting in energy loss. In severe cases, the reflected laser beam may burn the nozzle

(5) The water-cooling pipeline cannot completely cool the lower end of the nozzle, causing the place close to the molten pool to be easily damaged by radiant heat

(6) The protective mirror glass cannot be completely cooled, and local overheating may easily cause the glass to break

The main disadvantage is that the uniformity of the powder flow at the outlet of the nozzle is poor, and the powder is easy to melt and block the powder outlet at the outlet at the bottom end, and the nozzle cannot adjust the diameter of the powder convergence

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