LOCTITE 3614
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
- One-Component Heat-Cure Epoxy
- SMD Attachment Applications
- High Wet-Strength Processing
Product Description
LOCTITE® 3614 is a one-component, heat-curing epoxy adhesive specifically designed for attaching surface-mount devices (SMDs) to printed circuit boards (PCBs) before wave soldering operations. The red, high-viscosity adhesive delivers excellent wet strength, high dot profile retention and reliable electrical performance, making it suitable for medium-speed stencil printing processes. Once cured, LOCTITE 3614 provides strong mechanical bonding, high thermal stability and excellent resistance to wave soldering and environmental exposure, ensuring long-term reliability in electronic assembly applications.
Key Features & Benefits
- One-component epoxy adhesive requiring no mixing.
- Designed for SMD attachment prior to wave soldering
- High wet strength and excellent stencil-printing performance.
- Good electrical insulation characteristics after cure.
- Excellent resistance to wave soldering and solder-dip processes.
- High glass transition temperature for thermal durability
- Suitable for automated electronics manufacturing environments
Recommended Applications
- Bonding surface-mount devices (SMDs) to PCBs.
- Wave soldering assembly processes.
- Stencil-print adhesive deposition systems
- Electronic assembly applications requiring strong component retention.
- Small-part bonding and electronic packaging operations.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Appearance
Red viscous gel
Appearance at room temperature.
Density (g)
1.4 g/cm3
Specific Gravity
1.36
Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.
For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless.
Physical Properties
Viscosity
20,000 - 65,000 mPa.s
Viscosity is a measurement of a fluid’s resistance to flow.
Viscosity is commonly measured in centiPoise (cP). One cP is defined as
the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP.
A product like honey would have a much higher viscosity -around 10,000 cPs-
compared to water. As a result, honey would flow much slower out of a tipped glass than
water would.
The viscosity of a material can be decreased with an increase in temperature in
order to better suit an application
Thermal Properties
Glass Transition Temperature (Tg)
155 °C
The glass transition temperature for organic adhesives is a temperature region where the polymers change from glassy and brittle to soft and rubbery. Increasing the temperature further continues the softening process as the viscosity drops too. Temperatures between the glass transition temperature and below the decomposition point of the adhesive are the best region for bonding.
The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs.
Thermal Conductivity
0.3 W/m.K
Thermal conductivity describes the ability of a material to conduct heat. It is required by power packages in order to dissipate heat and maintain stable electrical performance.
Thermal conductivity units are [W/(m K)] in the SI system and [Btu/(hr ft °F)] in the Imperial system.
Electrical Properties
Volume Resistivity
1.8×10e+15 Ohms⋅cm
Volume resistivity, also called volume resistance, bulk resistance or bulk resistivity is a thickness dependent measurement of the resistivity of a material perpendicular to the plane of the surface.
Additional Information
Technical Properties
As-Supplied / Before-Processing Properties
| Property | Value | Unit | Condition |
|---|---|---|---|
| Technology | Epoxy | — | Surface mount adhesive |
| Appearance | Red Viscous Gel | — | Uncured |
| Specific Gravity | 1.36 | — | 25°C |
| Yield Point | 350 - 725 | Pa | 25°C |
| Casson Viscosity | 20 - 65 | Pa·s | 25°C |
| Components | One Component | — | No mixing required |
| Cure Type | Heat Cure | — | Recommended >100°C |
| Wet Strength | Very High | — | Stencil print application |
Technical Properties
After-Processing / Final-State Properties
| Property | Value | Unit | Condition / Method |
|---|---|---|---|
| Glass Transition Temperature (Tg) | 155 | °C | Fully cured |
| Coefficient of Thermal Expansion | 52 × 10⁻⁶ | K⁻¹ | ISO 11359-2 |
| Thermal Conductivity | 0.3 | W/m·K | ISO 8302 |
| Volume Resistivity | 1.8 × 10¹⁵ | Ω·cm | IEC 60093 |
| Surface Resistivity | 22 × 10¹⁵ | Ω | IEC 60093 |
| Dielectric Breakdown Strength | 40.1 | kV/mm | IEC 60243-1 |
| Lap Shear Strength (Steel) | ≥25 | N/mm² | ISO 4587, 30 min @ 150°C cure |
| Torque Strength (1206 Capacitor) | 30 - 70 | N·mm | IPC SM817, 5 min @ 125°C cure |
| Wave Solder Resistance | Pass | — | IPC SM817 @ 260°C |
