TiZr Passivation

Chrome Free Conversion Coating

What is TiZr passivation?

TiZr is shorthand for the titanium zirconium passivation process applied to aluminium components. This removes the natural oxide layer and replaces it with a stable, chemically modified ‘shield’ layer. Passivation is also referred to as conversion coating.

TiZr passivation creates a stable surface which will allow bonding and welding processes to deliver repeatable, strong, durable adhesive bonds. This conversion coating process also provides a stable base for powder coating and offers additional protection against corrosion. This is important in environments where the aluminium component may be exposed to moisture, chemicals, or high temperatures.

TiZr passivation and laser welding

TiZr is becoming increasingly popular as a pre-treatment for laser welding, the protective surface preventing unwanted oxidation around the weld zone. The clean, passivated surface promotes better laser absorption and a more consistent weld, reducing the risk of porosity, cracking, or defects in the weld seam.

Over 20 years’ experience in providing TiZr pre-treatments

As the first metal treatment provider in the UK to install TiZr as a chrome-free passivation process (since 2001), Powdertech Surface Science is the most experienced outsource TiZr pre-treatment provider in the country with an unrivalled body of knowledge. We use the latest Gardobond® systems for TiZr passivation and apply it to aluminium components (cast, extruded or formed) to enhance adhesive durability for metal-to-metal bonding and welding.

Powdertech TiZr matches anodising for enhanced adhesive bonding

Extensive testing shows that the stable, protective passivation layer achieved through Powdertech TiZr matches the performance of anodising for durability of adhesive joints.

TiZr pre-treatment has a faster lead time than anodising, uses less energy and is a more cost-effective and environmentally appropriate process than anodising.

Learn more in our white paper

Why choose Powdertech TiZr conversion coating?

Automotive OEM specifications

Our TiZr process meets the following Automotive OEM specifications for bonding:

JLR specification STJLR.50.5002B - with Gardobond® X 4591
Tesla specification TS-0002074 - with Gardobond® X 4707
VW/Audi specification TL82428
Morgan specification MMC 1.27
BMW 9702

Gardobond etch passivation techniques and Henkel Bonderite M-NT 2040 give equivalent levels of protection.

Prototype to full production under one roof

We have the capabiity and facilities at our plant to take your project from lab trials to prototype and then to full production. After lab-scale testing ( see equipment details below and on our ‘Our Facility’ page) we run a 7-stage pilot line for prototype part testing and coupon programmes. For full production we have two 14-stage full-sized immersion treatment lines with envelope of 4m x 1.5m x 0.5m.

Laboratory testing with XRF, RFU Spectrometer and Instron equipment

Your products will benefit from ongoing testing that we perform in our Surface Characterisation Laboratory with XRF UV-Florescence equipment and world leading Instron mechanical testing technology. Tests are performed on all the aluminium alloys we work with, from 3xxx series up to 7xxx series, and in all formats. We can test coupons and small test pieces in the early stages of your project.

Individual project advice

Test results enable us to work with you to understand the optimal surface finishing pre-treatment process you need to take bonding strategies to the next level, and to achieve repeatability going forwards. With over twenty years’ experience in TiZr pre-treatment we can advise our clients on a project-by-project basis.

Surface cleanliness

Surface contaminants will impair the performance of any adhesive or coating applied to the metal in terms of bonding performance and also aesthetics. By using XRF equipment Dyne inks and UV-Fluorescence we measure the level of aluminium surface contaminants prior to TiZr passivation.

We will always ensure that your metal is clean before any coating is applied.

Powdertech TiZr Case Studies

Commercial Case Studies

Advanced surface treatment technologies for lightweighting in electric vehicles

Two critical aluminium surface treatments delivered by Powdertech Surface Science feature in the Watt Electric Vehicle Company (WEVC) eCV1 electric van.

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TiZr enhanced bonding in Nichols N1A Supercar

We are extremely proud that our optimised TiZr passivation service has ensured secure bonding in the aluminium chassis of such a magnificent vehicle - the Nichols N1A Supercar.

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Optimised TiZr conversion coating for enhanced structural bonding.

Optimized TiZr passivation ensured strong aluminium panel bonding for the Morgan Super 3 chassis, and secure bonding on to powder coated interior door panels.

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The science behind TiZr passivation

For more in depth details we have a range of white papers to read and download:

Featured

The benefits of collaboration in surface treatment decisions

The benefits of solving powder coating issues in collaboration.

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TiZr pre-treatment as an alternative to anodising for bonding

Tests have conclusively demonstrated that the bonds formed after optimised carefully controlled TiZr pre-treatment give equivalent bond durability to those formed after anodising

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