3M™ Scotch-Weld™ Structural Adhesive EC-3448

  • Part Number EC-3448
  • 3M Product Number EC-3448
  • 3M ID 7000046471
  • UPC 00021200654299

Designed to bond pre-cured graphite epoxy composites

Excellent performance from -67°F (55°C) to 225°F (107°C)

Unusually high 180°F hot/wet durability

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  • Designed to bond pre-cured graphite epoxy composites
  • Excellent performance from -67°F (55°C) to 225°F (107°C)
  • Unusually high 180°F hot/wet durability
  • Non-Sagging thixotropic formula holds its shape for precise bond line control and less rework
  • This is a paste version of the 3M™ Scotch-Weld™ Structural Adhesive Film AF 163-2 Film

We developed 3M™ Scotch-Weld™ Epoxy Adhesive EC-3448 as a one-part epoxy adhesive that cures at 250°F for 60 minutes to form a tough, rigid bond. We formulated this thixotropic adhesive to meet aerospace bonding requirements on metal to metal and pre-cured fiber reinforced epoxy composite laminates.

EC-3448 being used in fuselage assembly to bond the aft pressure bulkhead retainer to the fuselage.
Bonds metal to metal and precured fiber-reinforced epoxy composite laminates
We designed 3M™ Scotch-Weld™ Epoxy Adhesive EC-3448 to be a low flow compound that is ideal for vertical or overhead surfaces with no run-off. It's a paste version of the 3M™ Scotch-Weld™ Structural Adhesive Film AF 163-2 Film. With its soft-paste viscosity it is easy to tool and form for a variety of applications. Workers will appreciate this one-part adhesive for its easy-to-dispense formula.

3M™ Scotch-Weld™ Epoxy Adhesive EC-3448 meets exacting bonding needs on metal to metal and pre-cured fiber reinforced epoxy composite laminates. It delivers excellent performance from -67°F (55°C) to 225°F (107°C) along with unusually high 180°F hot/wet durability. This adhesive is qualified to multiple aerospace customer specs to meet requirements in aircraft manufacture and MRO applications. It has outstanding environmental resistance as well, for a dependable, lasting bond.

The thick paste form allows you to spread the epoxy over large areas and still provide ample time to position parts for exact fit. Our non-sagging, formula holds its shape when dispensed and won't migrate, meaning little to no rework is necessary in overhead and other applications. Its thixotropic consistency provides greater bond line control for quality workmanship and to help minimize waste and excess weight. High impact resistance helps improve service life and reduce potential damage because this adhesive remains strong over time.

Epoxy adhesive applied to large aluminum honeycomb panels for structural bonding
3M Aerospace adhesives combine high mechanical strength with excellent durability
What Are Epoxy Adhesives?
3M™ epoxy adhesives are part of the class of adhesives called "structural adhesives," which also includes polyurethane and acrylic adhesives. Epoxy adhesives are typically formulated with reactive components (Base and Accelerator) that cure when mixed to form a solid plastic material. 3M provides epoxy adhesives in multiple formats to support your processing needs:

Two Part— In this format the Base and Accelerator are stored separately which enables the adhesive to have a long shelf life even when stored at room temperature. These materials are available in a duo-pak cartridges for use with the 3M™ EPX™ Applicator System, enabling you to simultaneously meter, mix and apply two-part adhesives. For larger scale operations, you can purchase these in bulk. Because these parts are mixed at point of use, you can reduce waste by saving non-mixed unused material for a later job.

One Part— In this format, we do the mixing for you and ship it frozen. You store it in a freezer, then remove and thaw it when you're ready to use it.

Adhesive Films — In this one-part format, we not only do the mixing for you, but we also turn it into a film that can be specifically cut to size and placed into your bond line. We offer a variety of films in different weights/thickness and supports. These films must be stored frozen.

In a two-part epoxy adhesive, once the two parts are mixed in their specified ratio, they begin the curing process and offer a limited working time where the adhesive can be applied and the two surfaces positioned as needed. Similarly, in a one-part adhesive there is a limited out time after which material is thawed during which it must be used. This work life or out time lasts anywhere from a few minutes to 48 hours or longer.

In general, epoxy adhesives provide high shear and peel strengths and have good environmental resistance. These adhesives are preferred for their ease of use, mechanical strength and chemical resistance. Depending on the formulation, epoxy adhesives can be flexible or rigid, transparent or opaque, quick setting or slow setting, high flow or low flow, room temperature or elevated temperature cure. Epoxy adhesives are among the strongest adhesives available, making them well-suited for jobs requiring strength and durability.

Our Best for Your Best
3M is proud to partner with organizations across the spectrum of aerospace and related industries. Enabling efficiencies, reducing process times and lowering aircraft weight is how we execute our never-ending mission to offer best-in-class adhesives, sealants, surface protection products and composite resins that effectively reduce costs on multiple fronts. Professionals across the industry know the numerous advantages of 3M Aerospace. Our brand is widely recognized for the highest standards of quality and performance, adding value to the final results. By engineering reliability, longevity and value into all of our products, we have a history of saving money by reducing waste, rework and time.

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