LOCTITE 680
Harmonization Code : 3506.10.00.00 | 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
Main features
- High-Strength Cylindrical Retention
- Gap-Filling Cylindrical Retention
- Heat and Fluid Resistance
Product Description
LOCTITE® 680™ is a one-component, high-strength anaerobic retaining compound designed for bonding close-fitting cylindrical metal parts where medium viscosity is preferred. The green methacrylate ester liquid cures when confined between mating metal surfaces in the absence of air, helping prevent loosening and leakage caused by shock and vibration. It delivers robust curing on active metals such as mild steel and passive substrates including stainless steel and plated surfaces, while tolerating minor contamination from cutting, lubricating, anti-corrosion, and protective oils.
Key features
- High-strength retention: Develops up to 28 N/mm² compressive shear strength on stainless-steel pins and collars after a seven-day cure.
- Gap-filling cylindrical bonding: Supports close-fitting metal assemblies and maintains useful strength across tested gaps from 0.05 to 0.25 mm.
- Heat and fluid resistance: Retains strength after exposure to motor oil, gasoline, brake fluid, water/glycol, ethanol, acetone, biodiesel, and diesel exhaust fluid.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Additional Information
As-supplied / before-processing properties
Typical properties of the uncured material; values are reference data rather than guaranteed product specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Technology | Acrylic | — | Uncured material |
| Chemical type | Methacrylate ester | — | Uncured material |
| Appearance | Green liquid | — | Uncured material |
| Fluorescence | Positive under UV light | — | Inspection aid |
| Components | One component | — | No mixing required |
| Viscosity classification | Medium | — | Retaining application |
| Cure mechanism | Anaerobic | — | Cures when confined between close-fitting metal surfaces without air |
| Secondary cure | Activator | — | May accelerate cure or support larger gaps |
| Strength classification | High | — | Cylindrical retaining application |
| Specific gravity | 1.1 | — | At 25°C; TDS value |
| Dynamic viscosity | 750–1,750 | mPa·s | Brookfield RVT, 25°C; spindle 3, 20 rpm |
| Dynamic viscosity | 650–1,850 | mPa·s | Cone and plate, 25°C; shear rate 129 s−1 |
| Dynamic viscosity | 450–550 | mPa·s | SDS value; method not stated |
| Density | 1.1 | g/cm³ | At 20°C; SDS value |
| Flash point | >100 | °C | SDS value |
After-processing / final-state properties
Typical cured-material properties depend on substrate, bond gap, temperature, activator use, cure time, surface condition, and test method.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Coefficient of thermal expansion | 52 × 10−6 | K−1 | ISO 11359-2 |
| Compressive shear strength | ≥24.1 | N/mm² | ISO 10123; steel pins and collars; cured 1 hour at 93°C and tested at 22°C |
| Compressive shear strength | ≥19.3 | N/mm² | ISO 10123; steel pins and collars; cured 24 hours at 22°C |
| Compressive shear strength | 26 | N/mm² | ISO 10123; steel pins and collars; cured 7 days at 22°C |
| Compressive shear strength | 28 | N/mm² | ISO 10123; stainless-steel pins and collars; cured 7 days at 22°C |
| Compressive shear strength | 16 | N/mm² | ISO 10123; aluminum pins and collars; cured 7 days at 22°C |
| Breakaway torque | 35 | N·m | ISO 10964; M10 black-oxide bolts and mild-steel nuts; cured 24 hours at 22°C |
| Prevail torque | 28 | N·m | ISO 10964; M10 black-oxide bolts and mild-steel nuts; cured 24 hours at 22°C |
| Motor-oil resistance | 145 | % initial strength | 5W40 synthetic motor oil at 125°C; 1,000-hour exposure |
| Unleaded-gasoline resistance | 110 | % initial strength | At 22°C; 1,000-hour exposure |
| Brake-fluid resistance | 110 | % initial strength | At 22°C; 1,000-hour exposure |
| Water/glycol resistance | 135 | % initial strength | 50/50 water/glycol at 87°C; 1,000-hour exposure |
| Ethanol resistance | 100 | % initial strength | At 22°C; 1,000-hour exposure |
| Acetone resistance | 100 | % initial strength | At 22°C; 1,000-hour exposure |
| B100 biodiesel resistance | 110 | % initial strength | At 22°C; 1,000-hour exposure |
| DEF resistance | 110 | % initial strength | AdBlue-type diesel exhaust fluid at 22°C; 1,000-hour exposure |
| E85 ethanol-fuel resistance | 105 | % initial strength | At 22°C; 1,000-hour exposure |
