CN112756813A

CN112756813A - Method for cutting stainless steel with thickness of 3mm by laser

Info

Publication number: CN112756813A
Application number: CN202110199500.2A
Authority: CN
Inventors: 王吉孝
Original assignee: Guangdong University of Petrochemical Technology
Current assignee: Guangdong University of Petrochemical Technology
Priority date: 2021-02-23
Filing date: 2021-02-23
Publication date: 2021-05-07

Abstract

The invention relates to a method for cutting 3mm stainless steel by laser, which comprises the following steps: removing oil stains and dust on the surface of the stainless steel, and keeping the surface of the stainless steel smooth; a ProCutter laser cutting gun is adopted to cut a 3mm stainless steel plate, and the process parameters are as follows: the cutting speed is 2-5 m/min; the laser power is 2.5-4 kW; the gas pressure is 1.2-1.8 MPa; the defocusing amount is-2-0 mm; the working distance is 0.6-1.0 mm; the diameter of the cutting nozzle is 2-3 mm; the cutting gas was nitrogen. The method of the invention is used for cutting stainless steel, and the cutting process window with no slag adhering to the back of the cutting seam, good cutting quality and the best cutting process parameter are obtained by changing each process parameter, and the stable and repeatable process is ensured.

Description

Method for cutting stainless steel with thickness of 3mm by laser

Technical Field

The invention relates to a method for cutting 3mm stainless steel by laser, in particular to a method for cutting a stainless steel plate with the thickness of 3mm by laser and nitrogen.

Background

304 stainless steel is a chromium-nickel stainless steel which is most widely used, and has good corrosion resistance, heat resistance, low-temperature strength and mechanical properties as a steel with wide application; good hot workability such as stamping, bending and the like, and no heat treatment hardening phenomenon (the use temperature is-196 ℃ below zero to 800 ℃). Corrosion resistance in the atmosphere, and timely cleaning to avoid corrosion if it is an industrial atmosphere or a heavily polluted area. Is suitable for processing, storing and transporting food. Has good processing property and weldability. Plate heat exchangers, corrugated pipes, household articles (class 1, 2 tableware, cabinets, indoor piping, water heaters, boilers, bathtubs), automobile parts (windshield wipers, mufflers, molded articles), medical appliances, building materials, chemicals, food industry, agriculture, ship parts, and the like.

Among stainless steels, the work hardening phenomenon is most prominent with austenitic and austenitic + ferritic stainless steels. For example, the strength sigma b of the austenitic stainless steel after hardening reaches 1470-1960 MPa, and the yield limit sigma s is increased along with the increase of sigma b; the austenitic stainless steel in the annealed state has sigma s not exceeding 30-45% of sigma b and reaches 85-95% after work hardening. The depth of the work hardening layer may be 1/3 or more of the cutting depth; the hardness of the hardened layer is improved by 1.4-2.2 times compared with the original hardness. Because the stainless steel has large plasticity, the product lattice is distorted during plastic deformation, and the strengthening coefficient is large; the austenite is not stable enough, and part of the austenite can be transformed into martensite under the action of cutting stress; in addition, the compound impurities are easy to decompose and disperse under the action of cutting heat, so that a hardened layer is generated during cutting. The work hardening phenomenon generated by the previous feeding or the previous working procedure seriously influences the smooth proceeding of the subsequent working procedure.

The conventional method of cutting stainless steel has many disadvantages: large cutting force, high cutting temperature, difficult breakage of chips, easy abrasion of cutters and large linear expansion coefficient. Based on the reasons, other cutting methods are adopted to obtain high-quality cutting seams, so that the cutting method has important significance and practical value, and an optimal cutting process window is not available for the stainless steel with the thickness of the plate at present.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a method for cutting 3mm stainless steel by laser, which takes 304 stainless steel as a research object and obtains high-quality cutting seams by using the laser cutting method.

The invention is realized by the following technical scheme: a method of laser cutting 3mm stainless steel, the method comprising:

(1) removing oil stains and dust on the surface of the stainless steel, and keeping the surface of the stainless steel smooth;

(2) a ProCutter laser cutting gun is adopted to cut a 3mm stainless steel plate, and the process parameters are as follows: the cutting speed is 2-5 m/min; the laser power is 2.5-4 kW; the gas pressure is 1.2-1.8 MPa; the defocusing amount is-2-0 mm; the working distance is 0.6-1.0 mm; the diameter of the cutting nozzle is 2-3 mm; the cutting gas was nitrogen.

(3) The manipulator is adopted to assist cutting in the cutting process, a walking route is preset, gas pressure is guaranteed not to be too high in the cutting process, and the cutting head is prevented from touching obstacles and being far away from inflammable materials.

The invention has the advantages that:

(1) the cutting seam is smooth and flat, no slag is attached, and the cutting seam quality is very good.

(2) The cutting nozzle has long service life, the maintenance period of the cutting gun is prolonged, and the cost is saved.

(3) The cutting speed is high, the production efficiency is improved, and the delivery according to the schedule is ensured.

(4) The method for cutting the stainless steel with the thickness of 3mm by the laser is relatively low in cost and relatively easy to realize the process, and further plays a reference role in cutting other stainless steel plates with different thicknesses.

Detailed Description

Example (b):

purchase 3 mm's 304 stainless steel panel, greasy dirt and dust are got rid of on the surface, and the panel location debugs the relevant equipment of laser instrument, and whether the inspection cutting head lens need be changed, whether the cutting nozzle damages, adjusts out of focus volume, sets up the manipulator parameter, prepares nitrogen gas, and the cutting process parameter is: the cutting speed is 3 m/min; the laser power is 3.5 kW; the gas pressure is 1.4 MPa; the defocusing amount is-2 mm; the working distance is 0.8 mm; the diameter of the cutting nozzle is 2.5 mm; the cutting gas was nitrogen. The cutting head is prevented from touching the barrier in the cutting process, and the flammable objects are far away in the cutting process, so that the equipment and personal safety are ensured.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A method of laser cutting 3mm stainless steel, the method comprising:

2. The method for laser cutting of 3mm stainless steel according to claim 1, wherein a robot is used to assist in cutting during the cutting process, a traveling path is preset, and it is ensured that the gas pressure cannot be too high during the cutting process, so that the cutting head is prevented from touching an obstacle and being far away from inflammable materials.