Online Consultation Parameter settings and precautions for laser cutting sheet metal
The parameter settings and precautions for laser cutting sheet metal directly affect the cutting quality, efficiency, and equipment lifespan. The following are key parameter analysis and operation points, providing targeted suggestions based on different material characteristics:
1、 Core parameter settings
1. Laser power (W)
Function: Determine the vaporization ability of the material. Insufficient power can easily lead to slag accumulation on the cutting surface, while excessive power may burn through the thin plate.
Setting principle:
Thin plate (≤ 2mm carbon steel/stainless steel): 80-150W (low power ensures smooth cutting);
Medium thick plate (3-10mm carbon steel): 200-400W (requires high-pressure auxiliary gas slag blowing);
Aluminum alloy/copper alloy: requires higher power (≥ 300W), and due to the high reflectivity of the material, multiple adjustments and matching are required.
2. Cutting speed (mm/s)
Function: If the speed is too fast, it will cause incomplete blowing of slag, and if it is too slow, it will intensify thermal deformation.
Formula reference: speed=power/material thickness x coefficient (carbon steel coefficient is about 0.8, stainless steel coefficient is about 0.6).
Example: When cutting 5mm carbon steel with a power of 300W, the speed is approximately 300/(5 × 0.8)=75mm/s, which needs to be fine tuned according to the quality of the light spot.
3. Auxiliary gas type and pressure (MPa)
Gas selection:
Recommended gas action pressure range for materials
Carbon steel oxygen (O ₂) supports oxidation and blows away slag 0.6-1.0
Stainless steel nitrogen (N ₂) protects the cut from oxidation and maintains a gloss of 0.8-1.2
Aluminum alloy argon (Ar)/N ₂ reduces splashing and prevents metal oxidation 1.0-1.5
Pressure control: Thick plates require high pressure (such as 1.0MPa for 10mm carbon steel), and thin plates require low pressure (0.8MPa for 2mm stainless steel) to avoid blowing over the workpiece.
4. Focal length (mm)
Function: Adjust the focal point position of the laser beam and affect the energy density.
Setting method:
Automatic focusing: The device comes with sensors for real-time calibration, suitable for mass production;
Manual focusing: The focal point of the thick plate is located 1-2mm below the surface of the material (such as 10mm carbon steel, focal point -1.5mm), and the focal point of the thin plate is flush with the surface.
5. Pulse frequency (Hz)
Applicable scenarios: Used for pulse cutting (such as non-metallic or fine machining), the higher the frequency, the higher the overlap rate of the light spot, and the smoother the incision.
Parameter Range:
Continuous cutting of carbon steel: no pulse required (frequency 0Hz);
Stainless steel micro hole cutting: frequency 50-200Hz, pulse width 0.5-2ms.
2、 Material characteristics and parameter adaptation
1. Carbon Steel
Difficulty: Thick plate cutting is prone to slag accumulation and requires high power and oxygen to assist combustion.
Optimize parameters:
5mm carbon steel: power 250W, speed 60mm/s, oxygen pressure 0.8MPa, focal point 0mm (surface);
10mm carbon steel: power 400W, speed 30mm/s, oxygen pressure 1.0MPa, focal point -1.5mm.
2. Stainless Steel
Difficulty: High melting point+easy to stick slag, requiring nitrogen protection.
Optimize parameters:
3mm stainless steel: power 180W, speed 80mm/s, nitrogen pressure 0.9MPa, focal point+0.5mm (slightly higher than the surface);
8mm stainless steel: power 350W, speed 40mm/s, nitrogen pressure 1.2MPa, focal point -1mm.
3. Aluminum Alloy
Difficulty: High reflectivity+fast thermal conductivity, prone to burrs.
Optimize parameters:
2mm aluminum alloy: power 200W, speed 70mm/s, argon pressure 1.0MPa, focal point+0.3mm;
Multiple cutting attempts are required to avoid excessive power causing material melting and accumulation.
4. Galvanized Sheet
Attention: The zinc layer evaporates and produces toxic gases when heated, and ventilation needs to be strengthened; The cutting speed should be 10-20% faster than carbon steel to prevent the zinc layer from burning through.
3、 Operation precautions
1. Equipment pre maintenance
Lens cleaning: Wipe the focusing lens and protective lens with anhydrous ethanol every day to prevent splashing from adhering and causing lens breakage;
Guide rail lubrication: Apply lithium based grease to the lead screw and guide rail every week to ensure motion accuracy (repeated positioning accuracy ≤± 0.03mm).
2. Workpiece clamping and calibration
Clamping requirements:
Thin plates (≤ 1mm) are fixed with vacuum suction cups to prevent vibration during cutting;
Medium thick plates should be pressed tightly with magnets or pressure blocks, with a distance of ≥ 50mm from the cutting line, to avoid thermal deformation affecting positioning.
Calibration steps:
Use a crosshair to calibrate the perpendicularity between the cutting head and the workbench (deviation ≤ 0.1mm/m);
After the first piece cutting, measure the perpendicularity (≤ 1.5 °) and roughness (Ra ≤ 12.5 μ m) of the cut with a projector.
3. Safety and Environmental Protection
Protective measures:
Wear laser protective goggles (OD4+level) to prevent damage to the retina from ultraviolet light;
Close the protective cover during cutting and prohibit direct viewing of the cutting area (laser wavelength 1064nm belongs to Class 4 danger level).
Exhaust gas treatment: Install smoke and dust purifiers with a filtration efficiency of ≥ 95% to prevent the inhalation of metal dust (such as alumina) that can harm health.
4. Batch production control
First piece three inspections: After cutting the first piece, check the dimensional tolerance (± 0.1mm), incision quality (no slag hanging, no erosion), and perpendicularity;
Process monitoring: For every 50 pieces cut, 1 piece is randomly inspected to observe changes in cutting speed (fluctuation ≤ 5%) and adjust gas purity in a timely manner (oxygen purity ≥ 99.5%).
4、 Common Problems and Solutions
Possible causes and solutions for the problem phenomenon
Severe slag deposition on the cutting surface, insufficient power/low gas pressure. Increase the power by 10-20% and increase the gas pressure by 0.1MPa
Excessive incision, slow ablation speed/focal shift, increased cutting speed, recalibrate focal position
The frequency of the small hole deformation pulse is too low/the air pressure is unstable. Increase the frequency to 100Hz and check the sealing of the air path
Cut the surface of the impermeable material with oxide scale/focal length error. Polish the surface and re measure the focal height
5、 Efficiency optimization techniques
Common edge cutting: Adjacent parts share the cutting edge, reducing idle travel time and increasing material utilization by 15-20%;
Micro connection technology: Leave 1-2mm connection points at the edges of the parts to prevent displacement after cutting, suitable for thin plate processing;
Batch nesting layout: Optimize layout with CAD/CAM software to reduce waste areas. It is recommended to leave a spacing of 3-5mm for thick plates and 1-2mm for thin plates.
By accurately matching material characteristics, dynamically adjusting process parameters, and strictly adhering to equipment maintenance and safety regulations, the accuracy and stability of laser cutting sheet metal can be greatly improved, while extending the service life of the equipment.
