3M EC-3515
Harmonization Code : 3214.10.00 | Putty and other mastics | Resin cements, caulking compounds and other mastics

Main features
- Lightweight Aerospace Void Filling
- Honeycomb Edge Sealing Control
- Flexible Ambient Or Heat Cure
Product Description
3M Scotch-Weld Void Filling Compound EC-3515 B/A FR is a two-part, low-density, flame-retardant epoxy compound for void filling, honeycomb-edge sealing, and abradable filling in aerospace interior structures. The 1:1 volume ratio produces a blue or black dough-like mixture with more than 90 minutes of work life for a 200 g batch. Processing can remain at room temperature, with cure completed in two days at 23 deg C or accelerated to five hours at 52 deg C. After cure, the material reaches Shore D 57 hardness and 21 MPa compressive strength at 24 deg C.
Key features
- Low Density Void Filling: A mixed density of 0.47 to 0.50 g/cm3 supports lightweight cavity filling.
- Edge Sealing And Finishing: The dough-like compound can fill honeycomb edges and abradable areas.
- Ambient Or Accelerated Cure: The epoxy cures in two days at 23 deg C or five hours at 52 deg C.
Applications
Aerospace honeycomb-edge sealing, structural void filling, abradable filling, and aircraft-interior repair within the qualified process.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Additional Information
As-supplied / before-processing properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Part B color | Blue or black | - | Epoxy component |
| Part A color | White | - | Modified amine component |
| Mix ratio by weight | 100:94 | B:A | Two-part system |
| Mix ratio by volume | 1:1 | B:A | Two-part system |
| Solids | 100 | % | Mixed compound |
| Mixed density | 0.47 to 0.50 | g/cm3 | Before cure |
| Work life | More than 90 | min | 200 g mixed batch |
After-processing / final-state properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Color | Blue or black | - | Cured |
| Hardness | 57 | Shore D | Cured |
| Compressive strength | 37 | MPa | Tested at -55 deg C |
| Compressive strength | 21 | MPa | Tested at 24 deg C |
| Compressive strength | 3.1 | MPa | Tested at 93 deg C |
| Compression modulus | 825 | MPa | Tested at 24 deg C |
| Room-temperature cure | 2 | days | At 23 deg C |
| Accelerated cure | 5 | h | At 52 deg C |





















