3M 8671HS Polyurethane Protective Tape TDS

, Review & Use in High End Composite Components

• 3M 8671HS was originally designed as an abrasion resistant retro-fit-stick coating as leading edge protection for military helicopter blades.
• Polyurethane Protective Tape can be used both in-mould or stuck on after part has been cured and is best applied to a matt surface.
• SCC offer advice on best practice and use of the tape for kit cutting, storage and application to get the best out of the material.
• If you’d like to used 3M 8671HS in one of your next high value manufacturing projects, give us a call and we’d be happy to help you find the best process and application method for you.

Background

3M 8671HS was originally designed as an abrasion and FOD (foreign object damage) resistant retro-fit and stick coating for leading-edge protection on military helicopter blades.

The tape has now found its role in a number of application due to it’s incredibly tough and wear resistant properties; and it’s ability to be manipulated, easily adhered and even stretched around components to conform to the shape.

Processing Advice:

3M 8671HS comes lined with an incredibly strong pressure sensitive acrylic adhesive that with a 79N/100mm peel strength on bare aluminium. However, through practice it is possible to improve on this adhesion 20-30% by abrading the surface with P800-1200 silicone carbide paper and proper cleaning of the surface with acetone and a lint-free cloth. Alternatively the surface can be shot blasted with a F400 grit silicon carbide, to achieve a similar matt finish.

3M 8671HS can also be cured in-mould with most medium temperature epoxy matrix resin systems in autoclave and has a maximum service temperature of 135℃. This provides an even stronger bond with the composite component due to the higher levels of consolidation between the composite and the tape.  This is great for creating aerodynamic parts that need extra localised protection and results in a completely smooth component without any lips or edges that could interfere with the aerodynamics of the component. However, this is best reserved for sacrificial component, or parts with a relatively short service life, because once the tape has become wore and needs to be replaced, this perfect finish is not easy to replicated.

Cutting

Polyurethane protective is also incredibly cut resistant and kit cutting the tape requires a finely tuned set-up to get accurate and clean cuts. We have found that reducing drag on the material and avoid material shift is a good approach to achieving accurate results. This can be improved by using a 60° plotter blade and running the cutter at 1-3 meters per minute with low pressure down force, but this also depends on other factors like the size of flat contact side of the tool holder and the amount of suction offered by the vacuum bed.

Storage & Cleaning

3M 8671HS normally comes boxed with a protective paper on both sides of the tape to keep the exposed edges fresh and to avoid contamination. This is especially important if the tape is being used for in-mould use, as contamination could potentially affect the final bond of the tape to the composite. Due to the incredibly ‘sticky’ nature of the pressure sensitive acrylic adhesive it is best stored in its original box.

Other use-cases

Polyurethane tapes are being increasingly used in Formula One and the high performance sports industry for the protection of critical components during races and events to prolong the life of components whilst on tour, or mitigate potential catastrophic failure due to the erosion of sensitive or structurally integral components.

Find Out More…

If you’d like to trial the use of 3M 8671HS in a future product and need advice on best practices, whether you’re a new or existing customer, give us a call and we’d be happy to help you find the best processing method for your application. Click here to get in contact.