SIKAFAST 3121
Harmonization Code : 3907.30.00.40 | Epoxy Mold Compounds containing by weight more than 70 % silicon dioxide
Main features
- Fast Five-Minute Open Time
- High-Ductility Structural Bonding
- Concealed-Joint Fastener Replacement
Product Description
SikaFast-3121 is a fast-curing, two-component methacrylate structural adhesive for high-strength fastening of concealed joints. The 10:1 volume-mix thixotropic paste has a five-minute open time at 23 deg C and develops strength within minutes after application. Its toughened cured profile includes 80% elongation and 10.5 MPa tensile lap-shear strength under ASTM D638 and CQP046-6 / ISO 4587. The adhesive bonds aluminum, stainless steel, galvanized steel, and fiber-reinforced polymers and can replace or complement rivets, screws, or welding in assembly applications. Bond thickness is controlled between 0.5 and 5 mm during application.
Key features
- Fast strength development: Strength builds within minutes after application
- Five-minute open time: Defines the assembly window at 23 deg C and 50% relative humidity
- Toughened structural profile: Typical cured properties include 80% elongation and 10.5 MPa tensile lap-shear strength
Applications
High-strength fastening of concealed joints; bonding aluminum, stainless steel, galvanized steel, and fiber-reinforced polymers; replacing or complementing rivets, screws, or welding.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Mechanical Properties
Additional Information
As-supplied / before-processing properties
Typical values for SikaFast-3121 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-3121 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 | |
| Mix ratio by weight | 7.4:1 | Part A:Part B | |
| Consistency | Thixotropic paste | Mixed adhesive | |
| 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 |
