This case shows how Himgo supported a German automotive supplier in resolving corrosion, coating instability, and adhesive failure issues for an outdoor vehicle emblem.
The final solution achieved 500-hour ASTM B117 salt spray performance, stable color consistency, and reliable adhesion under low-temperature conditions.
Project Overview
| Industry | Automotive |
| Location | Germany |
| Customer Type | Tier 2 automotive component supplier |
| Product | Zinc alloy 3D metal emblem |
| Application | Tailgate branding badge |
| Size | 85 × 28 mm |
| Thickness | 2.5 mm |
| Relief Height | 1.2 mm |
| Mounting | 3M VHB adhesive |
| Lead Time | ~6 weeks |
Application Scenario
The emblem is installed on vehicle tailgates and exposed to continuous outdoor conditions.
- Road salt exposure in winter
- UV exposure under European climate
- Temperature range from -20°C to 60°C
- Rain, humidity, and moisture cycles
- High-pressure washing with detergents
This environment creates combined risks of corrosion, coating degradation, and adhesive failure.
Customer Problem
- Corrosion appeared after 3–4 months
- Black coating faded under UV exposure
- Color inconsistency between batches
- Adhesive detachment in winter conditions
Engineering Challenges
- Balancing corrosion resistance and appearance
- Ensuring UV stability of coating
- Maintaining batch color consistency
- Achieving stable adhesion at low temperature
- Controlling die casting surface defects
Material & Process Decision
Zinc Alloy (Material)
Used to achieve a true 3D structure and stable geometry across batches.
Die Casting (Process)
Selected to produce 1.2 mm relief height with consistent dimensional control.
Nickel Electroplating (10–15 μm)
Improves corrosion resistance under salt exposure conditions.
UV-Resistant Coating
Maintains color stability under long-term UV exposure.
3M VHB Adhesive (0.8 mm)
Ensures stable bonding under temperature variation.
Key Manufacturing Parameters
- Relief Height: 1.2 mm
- Tolerance: ±0.15 mm
- Electroplating: 10–15 μm
- Adhesive Thickness: 0.8 mm
- Salt Spray: 500-hour ASTM B117
Testing & Validation
- Salt spray test (ASTM B117)
- UV aging test
- Coating adhesion test
- Adhesive peel strength test
- 100% visual inspection
ASTM B117 defines the testing environment and is used for corrosion comparison, not direct service life.
Results
- Passed 500-hour salt spray test
- Color variation controlled within ΔE < 1.5
- Yield rate above 98.5%
- Stable adhesion at -20°C
- No field failure after 6 months
When to Use This Solution
- Outdoor automotive applications
- Salt exposure environments
- High consistency branding requirement
- Adhesive mounting under temperature variation
