Laser Marking Application Case: Standard Marking on Aluminum and Aluminum Alloys
Laser Marking Application Case: Standard Marking on Aluminum and Aluminum Alloys
Equipment Configuration: Chuangxin MFP Series 20W / 30W / 50W Fiber Laser
Aluminum and its alloys are among the most widely used metals in industry, found everywhere from 3C electronics enclosures to automotive components. However, aluminum’s response to fiber laser marking is completely different from stainless steel—it is more “demanding.” This case focuses specifically on standard marking on aluminum to help you get started quickly.
I. Material Characteristics
Aluminum has a very high reflectivity (approximately 80-90%) for 1064nm fiber lasers, meaning most of the laser energy is reflected rather than absorbed. Therefore, aluminum marking requires higher power density than stainless steel.
Key differences:
- Marking color on aluminum is typically light gray to dark gray, and it is difficult to achieve the pure black effect seen on stainless steel
- Aluminum conducts heat extremely quickly, making heat dissipation fast; higher energy density is required
- High reflectivity poses a risk of back-reflection to the laser source, requiring the laser to have isolation protection
Differences between aluminum types:
| Aluminum Type | Marking Difficulty | Mark Effect |
| Bare aluminum (brushed / sandblasted) | Medium | Light gray to dark gray, average contrast |
| Anodized aluminum | Easy | White / light marks (removing oxide layer), good contrast |
| Die-cast aluminum | More difficult | Porous surface, marks may be uneven |
| Mirror-polished aluminum | Most difficult | Extremely high reflectivity, requires marking spray assistance |
II. Equipment Configuration
| Model | Laser Source | Power | Application Scenario |
| 20W Model | MFP-20W | 20W | Small batch, fine marking, anodized aluminum |
| 30W Model | MFP-30W | 30W | Medium batch, bare aluminum marking |
| 50W Model | MFP-50W | 50W | Large batch, deep engraving, high-contrast bare aluminum |
III. Parameter Reference
Bare Aluminum (Brushed / Sandblasted Surface)
#### 20W Model
| Parameter | Recommended Value |
| Power | 65-80% |
| Speed | 400-700 mm/s |
| Frequency | 25-45 kHz |
| Hatch Spacing | 0.03-0.05mm |
| Number of Passes | 1-2 |
#### 30W Model
| Parameter | Recommended Value |
| Power | 45-60% |
| Speed | 500-800 mm/s |
| Frequency | 25-45 kHz |
| Hatch Spacing | 0.03-0.05mm |
| Number of Passes | 1 |
#### 50W Model
| Parameter | Recommended Value |
| Power | 35-50% |
| Speed | 700-1000 mm/s |
| Frequency | 30-50 kHz |
| Hatch Spacing | 0.03-0.05mm |
| Number of Passes | 1 |
Anodized Aluminum
Anodized aluminum is much easier to mark—the laser only needs to remove the surface oxide layer to expose the natural aluminum color underneath, forming a high-contrast white mark.
| Parameter | 20W | 30W | 50W |
| Power | 25-40% | 15-30% | 10-25% |
| Speed | 1000-2000 mm/s | 1200-2500 mm/s | 1500-3000 mm/s |
| Frequency | 50-80 kHz | 50-80 kHz | 50-80 kHz |
| Number of Passes | 1 | 1 | 1 |
Note: Anodized aluminum marking should be done “gently”—excessively high power or slow speed will burn through the oxide layer, causing the mark to turn black or the edges to blur. Start with low power and work upward.
IV. Effect Characteristics
Bare Aluminum Marking
- Color: Light gray to dark gray
- Contrast: Medium, not as distinct as on stainless steel
- Feel: Slight tactile sensation
- Remarks: If high-contrast black marks are needed, bare aluminum cannot achieve this naturally; marking spray (such as Cermark) or anodized aluminum is required
Anodized Aluminum Marking
- Color: Bright white (removing oxide layer to reveal natural aluminum color)
- Contrast: Extremely high, black and white distinction
- Feel: Smooth, slight tactile sensation
- Remarks: This is the best visual effect solution for aluminum marking
V. Precautions
- High reflectivity risk: Aluminum is a highly reflective material; some laser energy will be reflected back to the laser source during marking. The Chuangxin MFP series has built-in isolators, but long-term high-power marking still requires attention to the laser source’s operating condition
- Surface cleaning: Aluminum surfaces are prone to oxidation; wipe with alcohol before marking to remove the oxide layer and oil
- Thin aluminum sheets: Sheets below 0.5mm are prone to deformation; reduce power, increase passes, or use heat dissipation fixtures
- Die-cast aluminum issues: Die-cast aluminum surfaces are porous; marks may be uneven; increase power or number of passes
- Mirror-polished aluminum: Has the highest reflectivity; it is generally recommended to treat the surface with fine sandpaper or sandblasting, or use marking spray
- 3C electronics product enclosures (anodized aluminum)
- Automotive component identification
- Aluminum alloy door and window hardware
- Electronic product heat sinks
- Industrial aluminum profile labels
- Aerospace component marking
- Anodized aluminum is the simplest solution for aluminum marking—low power, high speed, white marks, extremely high contrast
- Bare aluminum marking requires higher power, producing gray marks with average contrast. If black marks are needed, marking spray or anodized aluminum is recommended
- The higher the power, the higher the marking efficiency, but also the greater the reflection risk; laser source protection is important
VI. Application Scenarios
Summary:
*Actual results vary significantly depending on aluminum grade and surface treatment method. It is recommended to conduct sample testing before batch production.*
