SIKAFAST 321S
Harmonization Code : 3907.30.00.40 | Epoxy Mold Compounds containing by weight more than 70 % silicon dioxide
Main features
- Fast Five-Minute Open Time
- Built-In Bondline Spacing
- Stanchion and Assembly Bonding
Product Description
SikaFast-321 S is a shimmed, two-component methacrylate structural adhesive for stanchion and general assembly bonding. Incorporated 0.68 to 0.84 mm spacers maintain a uniform bond thickness, while the 10:1 volume-mix thixotropic paste provides a five-minute open time at 23 deg C. The cured material reaches 80% elongation and a typical tensile lap-shear strength of 10.5 MPa under ASTM D638 and CQP046-6 / ISO 4587. It is suited to concealed-joint fastening on aluminum, stainless steel, galvanized steel, and fiber-reinforced polymers, including assemblies where adhesive bonding replaces or complements rivets, screws, or welding.
Key features
- Controlled bond thickness: Incorporated 0.68 to 0.84 mm spacers maintain a uniform bondline
- Five-minute open time: Supports rapid assembly at 23 deg C and 50% relative humidity
- Ductile structural profile: Typical cured elongation is 80% with 10.5 MPa tensile lap-shear strength
Applications
Stanchion and general assembly bonding; high-strength fastening of concealed joints; bonding aluminum, stainless steel, galvanized steel, and fiber-reinforced polymers.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Mechanical Properties
Additional Information
As-supplied / before-processing properties
Typical values for SikaFast-321 S Part A, SikaFast-3081 N Part B, and the mixed adhesive system.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Part A density | 0.96 | kg/l | SikaFast-321 S Part A |
| Part B density | 1.30 | kg/l | SikaFast-3081 N Part B |
| Mixed density | 0.99 | kg/l | Calculated mixed value |
| Mix ratio by volume | 10:1 | Part A:Part B | |
| Consistency | Thixotropic paste | Mixed adhesive | |
| Spacer shim thickness | 0.68 to 0.84 | mm | Incorporated spacers |
| Application temperature | 10 to 35 | deg C | Substrate and adhesive range |
| Open time | 5 | minutes | CQP526-2; 23 deg C / 50% RH |
After-processing / final-state properties
Typical cured values for the mixed adhesive system.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Hardness | 65 | Shore D | CQP023-1 / ISO 48-4 |
| Tensile strength | 9 | MPa | ASTM D638 |
| Elongation at break | 80 | % | ASTM D638 |
| E-modulus at 0-5% elongation | 100 | MPa | ASTM D638 |
| Tensile lap-shear strength | 10.5 | MPa | CQP046-6 / ISO 4587 |
| Service temperature | -30 to 80 | deg C | CQP513-1 |
