Low contact resistance
per DVS 2929 as finished and after storage
Exceptional adhesive bonding performance
before and after aging
Adaptable Ti/Zr process
Optional as single-step etch and passivation
- Exceptional pre- and post-aging adhesive bonding performance
- Low contact resistance per DVS 2929
- Low coating weight (<10 mg/m? Ti and Zr)
- Etches and passivates in one step
- Ambient temperature operation
- Optimized for immersion with spray compatibility
- REACH, RoHS and ELV compliant
Interlox 4220 is engineered for high-performance aluminum components and is suitable for cast, stamped, and extruded alloys, providing a robust foundation for adhesive bonding, welding, painting, and conversion coating requirements. Typical application areas include:
- Structural castings and gigacastings
- Battery housings and aluminum components in electrified vehicles
- Thermal management components
- Body-in-white (BIW) components and other automotive aluminum assemblies
Interlox 4220
One process. Multiple applications. Maximum performance.
Interlox 4220 is a Ti/Zr thin film passivation designed to enable durability and joining performance on modern aluminum platforms. By forming a stable, thin film coating, it helps displace the naturally forming oxide on aluminum and provides a controlled surface condition that supports downstream operations, especially where low contact resistance and structural adhesive bonding are required.
A key advantage is its process versatility. Interlox 4220 can be operated as a traditional passivation step, or ? where beneficial ? as a single-step etch and passivation process to simplify the surface treatment sequence. This can reduce chemical demand and equipment footprint while maintaining the functional performance required for automotive aluminum components.
Interlox 4220 is also designed for production-friendly operation, including ambient-temperature processing, single-component make-up and replenishment, and straightforward control using pH and total acidity. It is optimized for immersion applications and compatible in spray applications when required.
What inspires us
Why we developed Interlox 4220
Your challenge
Modern aluminum components must meet multiple requirements at once: strong adhesion for paint and structural adhesives, corrosion durability, and reliable joining performance. Many OEM specifications also demand low contact resistance, including after storage (¡°shelf life¡±), so weldability is not compromised. Achieving these targets while keeping film build low and simplifying the process sequence is difficult with conventional approaches.
Our solution
Interlox 4220 addresses these needs with a thin-film Ti/Zr conversion coating designed for low coating weight and low contact resistance, while delivering exceptional pre- and post-aging adhesive bonding performance. Its adaptable process window allows tuning to diverse OEM requirements, and its option to etch and passivate in one step supports simplified, controlled surface treatment for complex aluminum platforms.
