AlfaTech: SurTec 650

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SurTec 650

SurTec 650 is a trivalent chromium (Cr III) surface conversion treatment designed to protect aluminium and its alloys from corrosion while maintaining the electrical properties of the material.

Due to its ability to improve the adhesion of subsequent coatings, such as paints and lacquers, SurTec 650 is widely used in the aerospace, automotive, electronics and telecommunications industries. The treatment can be applied to various aluminium alloys, both from sheet metal and castings, and is suitable for components of various sizes and geometries.

Passivation with SurTec 650 offers effective protection against corrosion, even in aggressive environments, and ensures a long life of the treated components.

Subsequent treatments

After the treatment, parts can be painted for additional protection and high quality aesthetics. Alfatech uses a network of qualified partners to carry out the painting within 48 hours of its treatment, guaranteeing the continuity of the production process and compliance with the customer's specifications by directly managing the order.

COATING FEATURES

Trivalent chromium (Cr III) conversion treatment, RoHS and REACH compliant
High corrosion resistance (over 336 hours in salt spray according to ISO 9227)
Excellent electrical conductivity of the substrate retained
Excellent adhesion for subsequent coatings (paint, e-coat, powder)
Applicable on aluminium alloys from machining, extrusion or casting

TREATABLE WEIGHTS AND MEASURES

Minimum dimensions: a few millimetres
Maximum cylinder dimensions: 950 mm - ø 450 mm - weight 450 kg
Maximum parallelepiped dimensions: 950x450x850 mm - weight 450 kg

TECHNICAL DETAILS

Reference standards	MIL-DTL-81706B, MIL-DTL-5541F, RoHS, REACH, LN 9368-3 ID-number 1108, DIN 50935-2 type A coating
Layer thickness	Below 1 µm
Visual appearance	Slightly iridescent (blue-bronze), varying according to alloy
Corrosion resistance	Up to 336 hours in neutral salt spray (ISO 9227)
Processing methods	Frame or rotary barrel, on aluminium alloys and castings

Reference standards: MIL-DTL-81706B, MIL-DTL-5541F, RoHS, REACH, LN 9368-3 ID-number 1108, DIN 50935-2 type A coating
Layer thickness: Below 1 µm
Visual appearance: Slightly iridescent (blue-bronze), varying according to alloy
Corrosion resistance: Up to 336 hours in neutral salt spray (ISO 9227)
Processing methods: Frame or rotary barrel, on aluminium alloys and castings

SECTORS OF APPLICATION

Aerospace (protection of structural components and aluminium coatings used in aircraft and satellites)
Automotive (treatment of aluminium parts for vehicles, such as body panels, chassis components and cooling systems)
Electronics (passivation of aluminium enclosures and heat sinks, providing corrosion protection and maintaining electrical properties)
Telecommunications (protection of aluminium structures and components exposed to adverse environmental conditions)
Construction (treatment of aluminium profiles and panels used in facades, windows and roofs)
Railway industry (protection of aluminium components used in railway vehicles and related infrastructure)
Naval industry (passivation of aluminium parts exposed to marine environments, preventing corrosion)
Chemical industry (treatment of aluminium equipment and containers used in chemically aggressive environments)

Download

In this section you can download the PDF for the specific process.

scheda-surtec-650.pdf

FAQ

What materials can SurTec 650 be applied to?

The treatment is specifically for aluminium and its alloys, including those from casting or extrusion.

Does SurTec 650 contain hexavalent chromium?

No, it is a trivalent chromium (Cr III) treatment, which complies with environmental regulations such as RoHS and REACH.

Does the treatment alter the electrical conductivity of the part?

No, on the contrary: one of the main advantages of SurTec 650 is that it maintains good electrical conductivity of the treated surface.

What is the corrosion resistance of SurTec 650?

Parts treated with SurTec 650 can achieve up to 336 hours in neutral salt spray (according to ISO 9227), depending on the alloy type and application conditions.

Can the treatment be applied before painting?

Yes, it is often used as a pre-treatment to improve the adhesion of liquid, powder or e-coat paints.

Can the treatment be applied manually?

Yes, in addition to dipping or spraying, SurTec 650 can also be applied by pad/cloth for localised or maintenance work.

What does the workpiece look like after treatment?

The surface takes on a slightly iridescent colour (blue to bronze), but the treatment is mainly functional and not aesthetic.