DOWSIL 3-6891
Harmonization Code : 2901.10.00.00 | Acyclic hydrocarbons; Saturated
Main features
- Machinable Abradable Rubber
- 0.95 Cured Specific Gravity
- Two-Hour 300 deg F Cure
Product Description
DOWSIL 3-6891 Abradable Sealant starts as a black, flowable one-part silicone and heat-cures into a low-density, flexible and machinable rubber. A Brookfield viscosity of 2,300 poise supports casting, troweling or injection with standard one-component equipment, while a two-hour cure at 300 deg F establishes the condition for the cured-property values. The cured material combines a specific gravity of 0.95, Shore A 71 hardness, 580 psi tensile strength and 0.24 W/(m K) thermal conductivity. Applications include abradable seals, compressor-blade rubstrips and high-temperature thermal insulation.
Key features
- Abradable cured rubber: The heat-cured material can be machined for controlled seal clearance.
- Low-density final state: Typical cured specific gravity is 0.95.
- Heat-cure processing: Cured-property values use a two-hour cure at 300 deg F.
Applications
Abradable seals, compressor-blade rubstrips and high-temperature thermal-insulation applications.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Mechanical Properties
Thermal Properties
Additional Information
As-supplied / before-processing properties
Typical as-supplied and storage properties. Values are not specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Physical form | Flowable liquid | As supplied | |
| Appearance | Black | As supplied | |
| Viscosity | 2300 | poise | Brookfield HAF #7 at 10 rpm |
| Shelf life | 12 | months | Original unopened container |
| Storage temperature | 15-40 | deg F | Original unopened container |
| Package size | 3.6 | kg | Pail |
After-processing / final-state properties
Typical properties after a two-hour cure at 300 deg F.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Physical form | Flexible rubber | After heat cure | |
| Specific gravity | 0.95 | After heat cure | |
| Durometer hardness | 71 | Shore A | After heat cure |
| Tensile strength | 580 | psi | After heat cure |
| Elongation | 70 | % | After heat cure |
| Lap shear adhesion | 320 | psi | Aluminum; 100% cohesive failure |
| Thermal conductivity | 0.24 | W/(m K) | After heat cure |
| Coefficient of thermal expansion | 1.75 x 10^-4 | m/m deg C | After heat cure |
