Laser direct forming bright powder active adjusting coaxial powder feeding nozzle

Abstract

The invention discloses a laser direct forming bright powder active adjusting coaxial powder feeding nozzle, and relates to the field of additive manufacturing, in particular to a laser direct forming bright powder active adjusting nozzle. The laser direct forming bright powder active adjusting coaxial powder feeding nozzle comprises a laser defocusing amount adjusting mechanism, a connecting sleeve and a powder defocusing amount adjusting mechanism; the laser defocusing amount adjusting mechanism is arranged on the upper portion of the inner side of the connecting sleeve, and the powder defocusing amount adjusting mechanism is arranged on the middle and the lower of the connecting sleeve. The feeding nozzle has the beneficial effects of being novel in structure, easy and convenient to machine, convenient to use, capable of achieving independent adjustment of light spots and powder spots and achieving light spot and powder spot size matching and the like; the novel laser direct forming bright powder active adjusting coaxial powder feeding nozzle integrates economy and practicability.

Description

technical field [0001] The optical powder active adjustment coaxial powder feeding nozzle for laser direct forming according to the present invention relates to the field of additive manufacturing, and specifically relates to an active optical adjustment nozzle for laser direct forming. Background technique [0002] With the increasingly urgent demand for precision and complex parts in the aerospace, nuclear energy, and ocean engineering manufacturing industries, the emerging additive manufacturing technology is developing rapidly in the manufacture of complex parts due to its flexibility and high efficiency. The existing metal laser additive manufacturing mainly has the following three methods: powder spreading type, coaxial powder feeding type and side shaft powder feeding type. Compared with the other two methods, the coaxial powder feeding type is flexible, fast, and Good quality and other advantages. The efficiency and quality of laser coaxial powder-feeding additive m...

AI Technical Summary

Problems solved by technology

However, when the laser spot size is larger than the powder spot size, the energy density will be too large, and defects such as pores are likely to occur, which will affect the quality of additively manufactured parts; when the laser spot size is smaller than the powder spot size, the air powder flow will not be completely transported Melt pool, low powder utilization rate, reducing additive manufacturing efficiency

[0003] At present, the existing coaxial powder feeding nozzles are divided into multi-channel coaxial powder feeding nozzles and conical ring type coaxial powder feeding nozzles. The coaxial powder feeding nozzle can adjust the laser spot size by adjusting the laser defocus, but the structure of the inner flow channel in this design is complex, the uniformity and convergence of the air and powder flow at the nozzle outlet are poor, and the air and powder flow angle cannot be adjusted according to the Spot size adjustment powder spot size

The patent of American General Company (US7358457) adopts a multi-channel coaxial powder feeding nozzle, and its shielding gas structure is ingeniously designed, but it is difficult to process small gradient holes in the powder tube of this design, and the incident angle of the powder tube cannot be adjusted, so the applicability is limited

The angle-adjustable four-tube coaxial powder feeding nozzle (CN1025540371A) used by Xi'an Jiaotong University for laser direct forming solves the problem that the angle of the powder tube cannot be adjusted. The size of the powder spots can be adjusted by adjusting the defocus of the powder, but it cannot Size adjustment spot size, complex structure, four powder tube angles cannot be adjusted synchronously

To sum up, the existing coaxial powder feeding nozzles cannot realize the active adjustment of the powder defocus amount and the laser defocus amount at the same time, and cannot adapt to the requirements of the manufacturing characteristics of the parts, resulting in a mismatch between the spot size and the powder spot size, resulting in powder material Waste, affecting the quality of additively manufactured parts and reducing processing efficiency

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