For the integrated coaxial shower nozzle of laser melting coating
Technical field
the present invention relates to a kind of integrated coaxial shower nozzle for laser melting coating, belong to field of laser cladding.
Background technology
laser melting coating and superlaser surface cladding, its physical process is, under the irradiation of High energy laser beam, substrate surface is melted rapidly, liquid metal forms a small-scale molten bath, in this molten bath, metal material originally mixes mutually with the powder be added, and forms the liquid-metal layer that one deck is new, treat laser beam through after, the temperature in molten bath reduces, and liquid metal cools rapidly, forms the solid-state cladding layer that one deck is new in metal surface.Laser melting coating can change the metallicity of this key position greatly, as hardness, wearability, heat resistance, corrosion resistance etc.
the main powder feeding technology of current industrial quarters in laser melting coating application is that paraxonic dusts, but belongs to split type shower nozzle because paraxonic dusts, and need two shower nozzles to cooperate simultaneously, be unfavorable for very much the processing of complex surface, therefore dusting with axiation becomes new developing direction.In recent years, on the basis that same axiation is dusted, protective gas is also added into the design of same axiation, creates the technology of powderject, protective gas integrated coaxial.A kind ofly to dust as figure 1 shows, the shower nozzle of protective gas integrated coaxial.But in the world, because the design of integrated coaxial shower nozzle is not yet perfect, therefore this technology also has one period of very long period of expansion.
as the integrated coaxial shower nozzle in accompanying drawing 1; the laser channeling 2 that it has the central authorities being opened in this shower nozzle, the protective gas passage 4 being opened in multiple powder channels 3 around laser channeling 2, being opened in powder channel 3 periphery; laser channeling 2, powder channel 3 and protective gas passage 4 are all relatively independent, are not communicated with mutually.Laser, powder, protective gas are from being gathered together after respective channel injection goes out shower nozzle and treating that the work piece surface of cladding carries out cladding.Powder channel of the prior art is straight channel as shown in Figure 1, central shaft around laser channeling 2 is uniformly distributed, the powder stream that each channel injection goes out concentrates on respective jeting area respectively, be difficult to the powder flow field forming even density, and distant to shower nozzle bottom of the convergent point of each powder stream, thus affecting cladding effect, a series of cladding result such as tension force, melting ratio, cladding height of laser molten pool is all difficult to be controlled.
Summary of the invention
in order to solve the problem, the object of the present invention is to provide a kind of for laser melting coating and the Coaxial nozzle of refrigerating function integration.
in order to reach above object, the technical solution used in the present invention is: a kind of integrated coaxial shower nozzle for laser melting coating, it has the centre gangway of the up/down perforation shower nozzle being opened in these shower nozzle central authorities, the bottom of centre gangway is infundibulate, powder overall channel is offered between the outer wall and the outer wall of shower nozzle of centre gangway, this powder overall channel comprises the hybrid channel running through shower nozzle bottom surface being positioned at shower nozzle bottom, multiple one end is connected with powder adding set the helical first passage that the other end is connected with hybrid channel, hybrid channel is infundibulate, and its cross section perpendicular to centre gangway central shaft is annular.
further, the height of hybrid channel on centre gangway central axis direction is 5cm ~ 8cm.
preferably, first passage twist.
more preferably, the rotational angle displacement of first passage is 170 ° ~ 280 °.
further, the central shaft of hybrid channel and the central shaft of centre gangway coincide.
further, multiple first passage is uniformly distributed around the central shaft of centre gangway.
further; shower nozzle offers the gas atmosphere inlet be connected with centre gangway; and multiple gas atmosphere inlet is positioned at the below of protective lens; laser enters the centre gangway of shower nozzle by protective lens; high voltage protective gas enters centre gangway by gas atmosphere inlet; and in centre gangway, form top-down flowing wind go out from central channel injection, and mix with the powder ejected from first passage, arrive the workpiece substrate surface treating cladding.
further, multiple gas atmosphere inlet is uniformly distributed around the central shaft of centre gangway.
further, gas atmosphere inlet and centre gangway connection in the vertical direction distance shower nozzle bottom are more than or equal to 5cm.
the present invention is used for the integrated coaxial shower nozzle of laser melting coating, by original rectilinear powder channel is designed to multiple spirality channel and funnel-shaped passage two parts, powder ejects from each first passage and enters hybrid channel and mix, eject shower nozzle from the annular mouth of bottom, hybrid channel again and form powder flow field, powder flow field is in the distribution in full symmetric in axial 360 °, the overall uniformity in flow field improves greatly, and powder flow field is more concentrated, density increases, the minimum convergent point in powder flow field and the Distance Shortened of shower nozzle bottom, thus improve the tension force of laser molten pool, melting ratio, a series of cladding result such as cladding height.
Accompanying drawing explanation
accompanying drawing 1 is the cross-sectional view of shower nozzle of the prior art;
accompanying drawing 2 is used for the cross-sectional view of the integrated coaxial shower nozzle of laser melting coating for the present invention.
number in the figure is:
1, shower nozzle; 2, laser channeling; 3, powder channel; 4, protective gas passage; 5, gas atmosphere inlet; 6, laser beam; 7, workpiece base material; 8, cladding layer; 9, protective lens; 10, the first chamber; 11, the second chamber; 12, focusing lens; 13, laser head; 14, first passage; 15, hybrid channel.
Detailed description of the invention
below in conjunction with accompanying drawing, preferred embodiment of the present invention is described in detail, can be easier to make advantages and features of the invention be readily appreciated by one skilled in the art, thus more explicit defining is made to protection scope of the present invention.
as can be seen from the structural representation of accompanying drawing 2, present embodiments provide a kind of integrated coaxial shower nozzle for laser melting coating, it has the centre gangway of the up/down perforation shower nozzle 1 being opened in these shower nozzle 1 central authorities, the bottom of centre gangway is infundibulate, powder overall channel is offered between the outer wall and the outer wall of shower nozzle 1 of centre gangway, this powder overall channel comprises the hybrid channel 15 running through shower nozzle 1 bottom surface being positioned at shower nozzle 1 bottom, multiple one end is connected with powder adding set the first passage 14 that the other end is connected with hybrid channel 15, hybrid channel 15 is in infundibulate, and its cross section perpendicular to centre gangway central shaft is annular.
centre gangway comprises and is positioned at the first chamber 10 and is positioned at the second chamber 11 be connected below the first chamber 10 and with the first chamber 10, first chamber 10 of centre gangway and the axial line in the second chamber 11 coincide, first chamber 10 be cylindrical or infundibulate, and the bottom bore in the first chamber 10 is less than or equal to the top bore in the second chamber 11.Second chamber 11, in infundibulate, prevents powder from entering centre gangway from the second chamber 11 bottom nozzle on the one hand, reduces spray regime during protective gas ejection on the other hand.
one end of gas atmosphere inlet 5 is connected with protective gas filling device, and the other end is connected with centre gangway.The quantity of gas atmosphere inlet 5 is preferably 3 or 4, and gas atmosphere inlet 5 is positioned at the below of protective lens 9, to prevent powder contamination protective lens 9.The central shaft of multiple gas atmosphere inlet 5 around the first chamber 10 is uniformly distributed, and forms the stable flowing wind of wind direction to make protective gas in centre gangway.
gas atmosphere inlet 5 is more than or equal to 5cm with centre gangway connection in the vertical direction distance shower nozzle 1 bottom; to ensure that protective gas forms the stable flowing wind of wind direction within it before centre gangway ejection; and then guarantee that powder is not rushed in centre gangway, also can ensure that protective gas fully mixes with powder after central channel injection goes out simultaneously.Gas atmosphere inlet 5 in the present embodiment is connected with the first chamber 10 of centre gangway, if ensure the distance of above-mentioned 5cm, gas atmosphere inlet 5 also can be offered and be that the second chamber 11 is connected.
first passage 14 is preferably 3 or 4, and is uniformly distributed around the central shaft of centre gangway, only draws one to show explanation in accompanying drawing 2.First passage 14 twist, and rotational angle displacement is 170 ° ~ 280 °, angular displacement size depends on the vertical length of the powdering inlet of first passage 14 to shower nozzle low side, conference is crossed in angular displacement, and to cause powder to flow in passage not smooth, even result in blockage, angular displacement is too small, improves DeGrain to prior art.The size at the powdering inlet place of first passage 14 is greater than the size at dust outlet place, to increase pressure during powder spray injection shower nozzle.
the central shaft of hybrid channel 15 and the central shaft of centre gangway coincide, the height of hybrid channel 15 on centre gangway central axis direction is 5cm ~ 8cm, if this highly too small powder can not fully mix, if the angle of inclination of hybrid channel 15 can be affected on the one hand lower than this excessive height, and then affecting the minimum convergent point in powder flow field and the distance of shower nozzle bottom, the consumption of powder can be larger on the other hand.
laser head 13 gives off laser beam 6; laser beam 6 enters the first chamber 10 of centre gangway through focusing lens 12 and protective lens 9; high voltage protective gas is from gas atmosphere inlet 5 centre gangway; and in centre gangway, form top-down flowing wind go out from central channel injection; powder ejects from each first passage 14 and enters hybrid channel 15 and mix; eject shower nozzle from the annular mouth of bottom, hybrid channel 15 again and form powder flow field, laser, protective gas, powder arrive the work piece surface treating cladding jointly.
by original rectilinear powder channel 3 is designed to multiple spiral first passage 14 and funnel shaped hybrid channel 15, powder flow field is in the distribution in full symmetric in axial 360 °, the overall uniformity in flow field improves greatly, and powder flow field is concentrated more, density increases, the minimum convergent point in powder flow field and the Distance Shortened of shower nozzle bottom, thus a series of cladding result such as tension force, melting ratio, cladding height improving laser molten pool.
above-described embodiment, only for technical conceive of the present invention and feature are described, its object is to person skilled in the art can be understood content of the present invention and implement according to this, can not limit the scope of the invention with this.All equivalences done according to Spirit Essence of the present invention change or modify, and all should be encompassed within protection scope of the present invention.