CN103056520A - Laser drilling method - Google Patents

Abstract

The invention provides a laser drilling method. The laser drilling method includes steps of (1), enabling a supercharging device to spray high-pressure gas or liquid to the surface of a workpiece to be drilled and forming a high-speed fluid layer on the surface of the workpiece; and (2), starting a laser device to emit laser beams to drill a hole on the surface of the workpiece. The flowing direction of fluid of the high-speed fluid layer is parallel to the surface of the workpiece. The laser drilling method has the advantages that the pressure on the surface of the machined hole is reduced by the high-speed fluid, so that molten materials in the machined hole and steam of the materials are quickly discharged; a plasma shielding effect is relieved by the high-speed fluid, accordingly, the laser drilling machining speed is increased, and the laser drilling machining quality is improved; and long-pulse laser can be used for drilling operation owing to the high-speed fluid layer, and the control cost is lowered.

Description

A kind of method for drilling holes

Technical field

The present invention relates to field of laser processing, refer in particular to a kind of method of in the laser drill process, utilizing the high-velocity fluid auxiliary bore hole.

Background technology

Laser boring is the laser processing technology that reaches the earliest practical, also is one of main application fields of Laser Processing.Along with developing rapidly of the modern industry and science and technology, use the material that hardness is large, fusing point is high more and more, and traditional processing method can not satisfy some technological requirement.For example, processing micron magnitude aperture on the refractory metal molybdenum plate; Aperture tens microns of hard tungsten carbide processing; At the spinning head of the deep hole of red, sapphire processing hundreds of micron and diamond wire-drawing die, chemical fibre etc.The processing tasks of this class is very difficult with the conventional mechanical processing method, sometimes or even impossible, then is not difficult to realize with laser boring.Laser beam is high concentration on room and time, utilizes lens focus, thereby spot diameter can be narrowed down to the laser power density that micron order obtains 105-1015W/cm2.So high power density almost can be carried out laser boring at any material, and compares with other method such as the conventional punching means such as machine drilling, spark machined, and have following significant advantage: 1) laser boring speed is fast, and efficient is high, and is good in economic efficiency.Because laser boring is to utilize power density for the high energy laser beam of l07-109W/cm2 material to be carried out snap, only have 10-3-10-5s action time, so laser boring speed is very fast.High-effect laser instrument is cooperated with high-precision lathe and control system, carry out programme-control by microprocessor, can realize the high efficiency punching.Laser boring is compared with electric spark-erosion perforation and machine drilling on different workpiece, and efficient improves l0-1000 doubly.

But existing method for drilling holes has following shortcoming: 1. slag is difficult to discharge when utilizing the large diameter hole of laser drilling; 2. processing metapore melt surface sputter thing much affects the quality in hole; 3. drilling quality is not good when using Long Pulse LASER boring, and is difficult for drilling through, and must shorten laser pulse has increased and control cost.

Summary of the invention

The present invention is directed to above-mentioned the deficiencies in the prior art, a kind of method of laser drill is provided; The method of this laser drill improved bore rate, improved the crudy in hole and reduced and controlled cost.

The present invention is achieved through the following technical solutions:

A kind of method for drilling holes may further comprise the steps:

(1) with supercharging device gases at high pressure or liquid are injected into the surface of the work that will hole and form one deck high-velocity fluid layer at surface of the work, the direction of flow of described high-velocity fluid layer is parallel to surface of the work;

(2) starting laser instrument sends laser beam and holes at surface of the work.

Laser action is when surface of the work, at first so that the evaporation of a part of material forms a small hole, then the further melted material of laser adds the degree of depth of macropore, at this moment the Various Complex composition is arranged in the hole, wherein main composition is: the workpiece material of melting (being in a liquid state), the workpiece material steam (being gaseous state) of evaporation, the plasma (excited electronic state) that laser and material vapor action form.Plasma expand at first rapidly and squit hole outside, near the aperture, form plasma cloud and cover the aperture, then under the effect of laser, melted material, material steam and plasma continue to increase in the hole, under the heat effect of these compositions at laser under the covering of plasma, sharply expand, and blast, these compositions finally mix spray portal outside.This blast meeting causes adverse effect to the quality in hole, as producing tension at empty inwall, forms crackle etc., and plasma has shielding action to laser, has reduced to shine the laser energy in the hole, so that laser energy can not utilize fully.

When adopting method for drilling holes boring of the present invention, there is the high-velocity fluid layer on the surface of workpiece, the evaporating materials that at first produces can be taken away rapidly, increased the evaporation rate of material, when the hole forms because the fluid velocity of hole surface is very high and be far longer than gas flow rate in the hole, so that the pressure in the hole is greater than the hole external pressure, the inside and outside mineralization pressure in hole is poor like this, so that the plasma of hole inner high voltage, outside material steam and melted material rapid expanding and the rapid tap, the outer composition of these taps again very fast being taken away by the high-velocity fluid layer makes it be difficult to form in the aperture screen layer, reduced like this plasma, material steam and melted material are to the shielding action of follow-up laser, thereby the utilization rate that improves laser energy has also improved the efficient of boring simultaneously.

To sum up, the present invention has following beneficial effect:

1. the high-velocity fluid layer is covered in surface of the work and is conducive to the slag in the hole is discharged, and has improved bore rate.

2. high-velocity fluid is taken away the heat that a part of laser produces, and has reduced the heat affected area of Laser Processing.

3. reduce vent surface sputter thing, improved the crudy in hole.

4. reduce the hole inner laser and induced the intensity of blast, prolonged the life-span in hole.

5. the high-velocity fluid layer has reduced and has controlled cost so that Long Pulse LASER also can carry out bore operation.

Description of drawings

The invention will be further described below in conjunction with drawings and Examples.

Fig. 1 is method for drilling holes schematic diagram of the present invention;

1, supercharging device; 2, workpiece; 3, injector head; 4, laser drill head; 5, laser beam; 6, high-velocity fluid layer;

The specific embodiment

Following examples are used for illustrating the present invention, but are not restriction the present invention.Describe the details of the method for the present invention's proposition in detail below in conjunction with accompanying drawing.

The invention provides a kind of method for drilling holes, as shown in Figure 1, injector head 3 is fixed on workpiece 2 tops at a certain angle; Need the position of holing on laser drill head 4 alignment pieces 2, injector head 3 should keep air-flow or the liquid of the ejection of certain distances and injector head 3 should be over against bore position with laser drill head 4; Open supercharging device 1, injector head 3 ejection gases or liquid form high-velocity fluid layer 6 on workpiece 2 surfaces, and the direction of flow of high-velocity fluid layer 6 is parallel to surface of the work; Starting afterwards laser instrument sends laser beam 5 and holes on workpiece 2 surfaces.

Claims (1)

1. a method for drilling holes is characterized in that, may further comprise the steps:

(1) with supercharging device gases at high pressure or liquid are injected into the surface of the work that will hole and form one deck high-velocity fluid layer at surface of the work, the direction of flow of described high-velocity fluid layer is parallel to surface of the work;

(2) starting laser instrument sends laser beam and holes at surface of the work.

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