In the processing of metal sheets, various laser cutting defects frequently occur due to factors such as material properties, equipment status, process parameters, auxiliary gas, environmental conditions, and operating methods. These laser cutting defects not only affect the product's appearance quality but also reduce dimensional accuracy, impact welding and assembly, increase rework rates, and directly affect the company's production efficiency and costs.

Therefore, establishing a systematic defect analysis and resolution system is one of the most crucial capabilities for laser cutting process engineers.

1. Classification Of Common Laser Cutting Defects

Common Laser cutting defects mainly include:

2. Comprehensive Guide to Burr Problem Solving

Burrs are one of the most common problems in laser cutting machine.

1) Main manifestations

- Metal adhesion at the bottom

- Rough edges

- Grinding is required afterward

- Affects welding and assembly

2) Causes of Burr Formation

- Insufficient power

Phenomenon:

- Incomplete cut

- Residual slag at the bottom

Solution:

- Increase laser power

- Reduce cutting speed

- Replace with a higher power device

- Excessive speed

Phenomenon:

- Molten metal cannot be discharged

- Stringing forms at the lower edge

Solution:

- Reduce cutting speed

- Increase auxiliary gas pressure

- Incorrect focus position

Phenomenon:

- Uneven cutting of upper and lower surfaces

Solution:

- Adjust focus height

- Use negative focus for thick plates

- Use zero focus or slightly positive focus for thin plates

- Insufficient gas pressure

Phenomenon:

- Slag cannot be blown out

Solution:

- Increase gas pressure

- Check for gas leaks

- Clean the gas filter

- Nozzle abnormality

Phenomenon:

- Airflow deviation

- Unstable kerf

Solution:

- Replace the nozzle

- Correct nozzle concentricity

- Clean nozzle slag

3. Comprehensive Solutions to Slag Retention Problems

Slag Retention Classification:

- Hard Slag

Characteristics:

- Difficult to remove

- Firmly adhered

Causes:

- Insufficient power

- Too high a focal point

- Insufficient air pressure

- Soft Slag

Characteristics:

- Easily detached

- Slightly affected

Causes:

- Unstable airflow

- Mismatched cutting speed

4. Solutions to Edge Burning Problems

1) Edge Burning Manifestations

- Yellowing of the cut

- Blackening of the edge

- Expansion of the heat-affected zone

2) Main Causes

- Too slow speed

Solution:

- Increase the cutting speed

- Optimize the acceleration

- Too high power

Solution:

- Reduce the power output

- Optimize duty cycle

- Focus too deep

Solution:

- Adjust focus position

- Insufficient oxygen purity

Solution:

- Use high-purity oxygen

- Check the gas supply system

5. Solutions to the problem of hole bursting

1) Causes of hole bursting

Hole bursting usually occurs in:

- Thick plate perforation

- High reflective materials

- High-power equipment

Manifestations:

- Metal spatter

- Surface bursting point

- Lens contamination

2) Solutions

- Use progressive perforation

Advantages:

• Reduce heat concentration

• Reduce bursting point

- Reduce initial power

• Function: Reduce instantaneous energy impact

- Increase pre-perforation time

• Function: Improve perforation stability

- Optimize air pressure

• Function: Improve slag discharge stability

6. Complete solutions to incomplete cut

1) Typical manifestations

• Partial connection

• Inability to separate sheet metal

• Bottom residue

2) Cause analysis

Insufficient power

Solution:

• Increase power

• Reduce speed

Lens contamination

Solution:

• Clean the protective lens

• Replace the focusing lens

Focus error

Solution:

• Recalibrate the focus

Insufficient air pressure

Solution:

• Increase the auxiliary gas pressure

7. Solutions to the problem of tilted cut

1) Problem manifestations

• Wide at the top and narrow at the bottom

• Narrow at the top Bottom width

• Inclined cut surface

2) Main causes

Abnormal beam mode

Solution:

• Check laser mode

Focus offset

Solution:

• Calibrate focus center

Nozzle eccentricity

Solution:

• Adjust concentricity

8. Comprehensive solutions to thermal deformation problems

1) Causes of thermal deformation

• Excessive heat input

• Inappropriate layout

• Dense cutting of small parts

2) Solutions

Optimize cutting path

• Segmented cutting

• Skip cutting

• Symmetrical cutting

Reduce heat input

• Increase speed

• Reduce dwell time

Increase micro-connections

Function:

• Prevent parts from warping

9. Lens Contamination Problem Solutions

1) Lens Contamination Symptoms

- Power Decrease

- Unstable Cutting

- Difficulty Drilling

2) Main Causes

- Splatter from Excavated Holes

- Impure Gas

- Abnormal Cooling

- Lack of Maintenance for an Extended Period

3) Solutions

- Regularly Replace Protective Lenses

- Use High-Purity Gas

- Check the Cooling System

- Properly Install Lenses

10. High-Reflectivity Material Back lighting Problems

1) Common Materials

- Aluminum Plate

- Copper Plate

- Brass

2) Risks

- Damage to Laser

- Burning of Lenses

- Abnormal Optical Path

3) Solutions

- Use Anti-High-Reflectivity Materials Laser

- Employs high-reflectivity dedicated process

- Optimizes perforation logic

- Improves sheet metal absorbance

11. Auxiliary Gas Abnormalities

1) Gas Pressure Fluctuations

Impact:

- Unstable cutting

- Increased burrs

Solution:

- Pressure stabilization system

- Check pipeline

2) Insufficient Gas Purity

Impact:

- Yellowing

- Oxidation

Solution:

- Replace with high-purity gas

- Check gas source

12. Typical Laser Cutting Defects of Different Materials

1) Common Problems with Carbon Steel

- Slag adhesion

- Oxidation

- Corrugation in thick plates

2) Common Problems with Stainless Steel

- Burrs

- Yellowing

- Insufficient shine

3) Common Problems in Aluminum Plate Cutting

- Reflective Light

- Hole Bursting

- Rough Cut

4) Common Problems in Copper Plate Cutting

- High Reflectivity

- Difficult Drilling

13. Typical Problems in Thick Plate Cutting

Common Problems:

- Long Drilling Time

- Bottom Slag

- Coarse Cut Surface Stripes

- Poor Perpendicularity

Solutions:

- Use High-Power Equipment

- Optimize Negative Focus

- Increase Nozzle Size

- Improve Airflow Stability

14. Problems in High-Speed Thin Plate Cutting

Common Problems:

- Edge Burning

- Vibration

- Small Hole Deformation

Solutions:

- Increase Acceleration

- Optimize Flying Cut

- Reduce Heat Accumulation

15. Process Debugging Logic

Excellent process engineers typically debug using the following logic:

- Confirm material

- Confirm thickness

- Select gas

- Set power

- Set focus

- Adjust speed

- Adjust gas pressure

- Inspect cut surface

- Fine-tune parameters

- Establish parameter database

16. Trends in Intelligent Defect Diagnosis

Future laser cutting defects handling will develop towards:

- AI intelligent diagnosis

- Automatic process correction

- Online monitoring

- Intelligent visual recognition

- Automatic focusing

- Intelligent gas pressure compensation

- Digital process database

17. Conclusion

Laser cutting defects are not terrible. What is terrible is the lack of systematic analysis capabilities.

Truly excellent laser cutting technology is not just about "being able to cut," but more importantly:

- Stable cutting over long periods

- High-efficiency production

- High-quality cut surface

- Low rework rate

- Low material cost

- High level of automation

- Replicable process management

In the future, with the development of high-power lasers, intelligent process databases, and AI-powered automatic machine adjustment, laser cutting will enter a new stage of greater intelligence, standardization, and efficiency.