3M AC-380
Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other
Main features
- Fuel Tank Sealing Performance
- Thixotropic Application Control
- Selectable Assembly Work Life
Product Description
3M Aerospace Sealant AC-380 Class B is a two-part, manganese-dioxide-cured polysulfide sealant for aircraft fuel tank and fuselage sealing. The thixotropic Class B paste can be extruded, injected, or applied by spatula, helping it stay in place during assembly. B-1/2 and B-2 grades provide different application-life and cure schedules while sharing a 100:10 base-to-accelerator mix ratio by weight. After cure, the dark-gray sealant combines low density, flexible Shore A hardness, and service capability across a broad aerospace temperature range.
Key features
- Fuel Tank Sealing: The polysulfide chemistry supports compatible aircraft fuel tank and fuselage joints.
- Thixotropic Class B Paste: The mixed sealant supports extrusion, injection, and spatula application.
- Selectable Work Life Grades: B-1/2 and B-2 schedules support different assembly windows.
Applications
Aircraft fuel tank and fuselage sealing by extrusion, injection, or spatula application.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Thermal Properties
Other Properties
Additional Information
As-supplied / before-processing properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Base color | Off white | - | Before mixing |
| Accelerator color | Black | - | Before mixing |
| Mix ratio by weight | 100:10 | base:accelerator | Class B system |
| Nonvolatile content | 97 | % | Typical |
| Base viscosity | 10000 to 14000 | poise | Brookfield RVT, spindle 7, 2 rpm, 77 deg F |
| B-1/2 schedule | 0.5; 5; 5 | h | Application life; tack-free time; cure time at 77 deg F and 50% relative humidity |
| B-2 schedule | 2; 8 to 10; 8 to 10 | h | Application life; tack-free time; cure time at 77 deg F and 50% relative humidity |
After-processing / final-state properties
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Color | Dark gray | - | Cured 14 days at 77 deg F and 50% relative humidity |
| Specific gravity | 1.1 | - | Cured |
| Hardness | 45 to 50 | Shore A | Cured |
| Low-temperature flexibility | No checking or adhesion loss | - | At -62 deg C |
| Service temperature range | -62 to 121 | deg C | Cured sealant |
| Short-duration temperature range | -62 to 182 | deg C | Cured sealant |
