CN1121453A

CN1121453A - Methods of cutting materials

Info

Publication number: CN1121453A
Application number: CN95104196A
Authority: CN
Inventors: W·奥尼尔
Original assignee: BOC Group Ltd
Current assignee: BOC Group Ltd
Priority date: 1994-10-26
Filing date: 1995-04-28
Publication date: 1996-05-01
Also published as: GB9421526D0; KR960013549A; JPH08118053A

Abstract

The invention provides a material cutting method. The part of the surface of a workpiece, which is cut, is heated to a temperature between the ignition point and the melting point of the workpiece by a laser beam which is defocused, and then is sprayed by pressurized oxygen or rich oxygen injection airflow, thus obtaining the incision with clean and tidy edges and excellent surface smoothness.

Description

Methods of cutting materials

The present invention relates to a kind of methods of cutting materials, particularly use a kind of method of the thick shaped steel of low power laser cutter cuts.

As you know, laser cutting process is that the laser beam that power is quite high focuses on the process on the material surface to be cut.The energy of laser is kept material and is made it to be under its fusing point, blows down the material that melts with jet-stream wind at a high speed, thereby severs an otch.This known method is all used the laser energy at the entire depth of otch, thereby will cut out the laser beam that qualified otch just needs the high power high-quality.

The objective of the invention is to improve the particularly efficient of thick shaped steel of low power laser cutting, promptly, utilize hyperbaric oxygen or oxygen enrichment jet-stream wind on cut surface, to obtain the otch of edge neatly and orderly and the surface smoothness of high-quality simultaneously by laser beam being scattered to improve the temperature of material to be cut.

Methods of cutting materials of the present invention comprises the following steps: with the laser beam that defocuses, disperse the surperficial position of material to be heated to temperature between its burning-point and the fusing point, and sprays this position with the oxygen or the oxygen enrichment jet-stream wind that pressurize.

The power output of laser instrument is preferably between 500 watts and 2000 watts, and the pressure of oxygen-enriched stream is preferably between 7 crust and 8 crust.In a most preferred embodiment, the position that laser beam heated is greater than position that jet-stream wind sprayed.

Referring now to description of drawings one embodiment of the present of invention.In the accompanying drawing:

Fig. 1 is the perspective view of laser cutting nozzle and workpiece to be cut;

Fig. 2 is the profile of Fig. 1 laser cutting nozzle;

The graph of relation of cutting speed and material thickness when Fig. 3 is 800 watts of laser instruments of employing.

As shown in Fig. 1 and Fig. 2, the inventive method has a lens mount 2 in order to the cutting nozzles 1 of the shaped steel that cuts thick about 45 millimeter, and lens 4 are equipped with in the inside, for the usefulness that focuses on the light beam that 800 watts of laser instrument (not shown)s launch.Nozzle 6 fixedly dangles in the lower end of lens mount 2 (as shown in the figure).Nozzle 6 with respect to lens 4 be configured to and geometrical condition is designed so that can focus on before jet expansion behind the laser beam scioptics 4, thereby when leaving nozzle 6, scatter.

Lens mount 2 has an aperture 8, passes through for the oxygen or the oxygen-enriched stream of pressurization, and air-flow then leaves nozzle through jet expansion with pattern.

During use, with workpiece to be cut 10, for example thick shaped steel, be placed under the nozzle 6, and apart from nozzle 6 one segment distances, make the laser beam that defocuses, disperses that leaves jet expansion be ejected into the surperficial position of workpiece, make the temperature at this position bring up to the burning-point of steel and the temperature between the fusing point.Simultaneously, make oxygen or the oxygen-enriched stream of pressure between 7 crust and 8 crust pass through aperture 8 and jet expansion, make itself and steel react and blow down the steel material of fusing, thereby form otch.

Typical case with said method when Fig. 3 shows with 800 watts of laser instrument cutting 43A mild steel cuts characteristic curve.

Cutting performance in the time of can finding out with 800 watts of laser instruments by this figure line, but can infer, also can use the laser instrument that is low to moderate 500 watts of power outputs.

The special benefits of cutting thick shaped steel with said method is:

A) can adopt lower powered laser instrument;

B) workpiece need not preheating;

C) laser instrument is easy to control, so the otch top edge can not producing when resembling the flame cutting

The phenomenon of fusing;

D) this method is fit to the non-directional cutting very much.

Self-evident, the superpower laser of employing 2 to 5 multikilowatts, the thicker workpiece of available said method cutting.

Claims

1. methods of cutting materials is characterized in that comprising the following steps: with the laser beam that defocuses, disperses the surperficial position of material being heated to temperature between its burning-point and the fusing point, and sprays described position with the oxygen that pressurizes or the jet-stream wind of oxygen enrichment.

2. the method for claim 1 is characterized in that, the power output of laser instrument is at least 500 watts.

3. method as claimed in claim 1 or 2 is characterized in that, material to be cut is thick shaped steel.

4. as the described method of 1 to 3 arbitrary claim, it is characterized in that the pressure of described oxygen or oxygen-enriched stream is between 7 crust and 8 crust.

5. as the described method of 1 to 4 arbitrary claim, it is characterized in that, described by position that laser instrument heated greater than position that jet-stream wind sprayed.

6. aforesaid basically methods of cutting materials.