As electronic devices become more powerful and compact, heat generation is a significant concern. Excessive heat threatens the reliability and longevity of electronic devices and components. This is where effective thermal management plays a crucial role. Thermal management involves using thermally conductive materials, such as epoxy resins, to manage and dissipate heat in electronic components, ensuring devices operate within safe temperature ranges to maintain reliable mechanical and thermal performance and longevity. Encapsulant materials with high thermal conductivity are crucial for effective thermal management in electronics packaging and devices. Thermal management applications include encapsulation and potting, adhesives, and coatings.
This blog explores the benefits of epoxy as a thermal management material and key considerations to consider when choosing an epoxy system for your application.
The Role of Epoxy Resin in Thermal Management
Epoxy resin is a thermosetting polymer material commonly used for various applications within electronic devices and assemblies. Its key thermo-mechanical properties play an important role in the performance and reliability of electronics packaging and devices to ensure proper thermal management:
1. High Insulation Performance
Epoxy resin is known for its exceptional insulation properties. It provides a barrier against electrical currents, which helps prevent short circuits and electrical malfunctions to ensure the reliability and safety of electronic devices, while managing heat dissipation. Epoxy has excellent thermal stability and can withstand high temperatures without degradation. Heat in excess of the intended operating temperature range can cause immediate catastrophic failure or eventual failure of the electronic component or device, as well as potential degradation of the epoxy, leading to loss of mechanical strength and adhesion properties. By keeping safe temperature ranges with effective thermal management, such failures or degradation may be avoided, and the potential for fire is reduced.
2. Enhanced Thermal Conductivity
Epoxy resin is formulated with thermally conductive fillers, such as aluminum oxide, boron nitride, copper, silver, graphite, or composites, to enhance its thermal conductivity. Heat is transferred by conduction when adjacent atoms vibrate against one another, or as electrons move from one atom to another. Conduction is the most significant means of heat transfer within a solid or between solid objects in thermal contact. The filler conducts heat away from the source, creating continuous pathways for the heat to travel from hot areas to cooler areas, thereby protecting the device from overheating and potential failure. In short, improved thermal conductivity facilitates high heat dissipation through the efficient transfer of heat away from electronic components, mitigating the risk of overheating and ensuring optimal performance and longevity.
3. High Mechanical Strength with Increased Durability
Epoxies are two-part thermosetting polymers composed of a resin, typically bisphenol-A (BPA) or bisphenol-F (BPF), or epoxy novolac, and an amine hardener. A chemical reaction, polymerization (curing), is initiated when the resin is mixed with a hardener (sometimes referred to as a catalyst). Epoxy resins form crosslinks during this process, creating a three-dimensional polymer network of great mechanical strength. The chemical composition of epoxy resin creates a strong, durable material with high mechanical strength suitable for electronic applications. Epoxy resin provides mechanical support to delicate electronic components, protecting components from physical damage and ensuring their longevity under various operating conditions.
4. Improved User Experience
Excessive heat can make electronic devices uncomfortable to use, or too hot to handle, as well as impact their performance. Thermal management maintains comfortable device use and device functionality by protecting from excessive heat.
Key Factors in Selecting Thermal Management Materials
When selecting thermal management material for a particular application, the specific thermal, mechanical, electrical, and environmental requirements of the application must be considered. The key factors include:
Heat Dissipation
Excessive heat or thermal stress can degrade electronic components and devices and reduce their lifespan. The specific heat dissipation needs of an application will determine the type of epoxy resin and filler materials required. Higher heat loads may necessitate materials with superior thermal conductivity. The epoxy must efficiently dissipate the heat generated by the electronic component or device or other heat source. The encapsulation of electronic components with thermally conductive epoxy can dissipate heat generated by the components more effectively, to reduce the risk of thermal damage by maintaining a uniform temperature.
Adhesive Requirements
Epoxy resins provide strong adhesion to various substrates, including metals, plastics, and ceramics. This ensures reliable bonding and thermal transfer between components and is particularly important in applications where materials must withstand vibrations and mechanical stress. The epoxy must have the mechanical strength and flexibility to endure any mechanical stress or thermal cycling to which it is subjected, without degradation or failure.
Mechanical stresses or failure can be caused by differences in coefficients of thermal expansion (CTE) of the epoxy and that of the electronic components and substrates in the electronic packaging. Thermal stress related failures due to CTE mismatch are particularly an issue for high power devices. Matching the coefficient of thermal expansion for the component to that of the substrate to that of the epoxy reduces thermally induced stresses and minimizes the risk of failure or delamination.
Viscosity
The viscosity of the epoxy resin affects its ease of application and the ability to fill gaps and voids in electronic assemblies. Low-viscosity materials are suitable for potting and encapsulating, while higher-viscosity resins may be better for adhesive applications. Selecting the appropriate viscosity ensures proper coverage and effective heat transfer.
Environmental Challenges
Thermal management materials must withstand environmental factors such as humidity, moisture, temperature fluctuations, and chemical exposure. This ensures long-term reliability and performance in harsh conditions. Epoxies are resistant to many chemicals and are therefore suitable in many harsh environmental conditions. The epoxy must resist the environmental contaminants that it will be exposed to in its operating environment.
United Resin’s Range of Thermal Management Materials
United Resin offers a comprehensive selection of epoxy resin systems for thermal management in electronic applications to achieve superior performance for electronic components, devices, and applications. Our signature products include:
EL-Cast VFR Plus
United Resin’s EL-CAST VFR PLUS is our latest innovation, emphasizing fire safety. This filled, low-viscosity, high-temperature potting and encapsulating resin provides superior flame resistance. With certain hardeners, it achieves a 0-second AfterFlame and has no flame drip, making it safer in high-risk environments. It is also easy to mix, simplifying the preparation process.
EL-Cast 1-F-5 TAB VO
This is a high-viscosity, high-temperature, one-component system designed with low odor and provides good air release, improving the working environment. This resin also provides a high-gloss finish and good thermal conductivity, and is commonly used for encapsulating “chip-on-board” applications.
EL-Cast 1-F-5 TAB, TAB SR
These medium-viscosity electronic resins can function as a one- or two-component system. They offer excellent thermal conductivity, high-temperature resistance, good chemical resistance, and excellent adhesion at high temperatures. These resins can be cured at room temperature or with heat and are suitable for transformers, filters, coils, and any applications where heat cure is feasible.
EL-Cast 760
EL-CAST 760 is a medium-viscosity, high-temperature potting and encapsulating resin with excellent impact and thermal shock resistance. It also offers high thermal conductivity and deflection temperature, making it well-suited for control units, transformers, noise filters, and similar applications.
E-CAST F-82
This unfilled, low-viscosity resin is known for its high-strength adhesion and good air release. It is ideal for intricate applications such as circuit boards and other detailed tasks.
Unlock Superior Thermal Management With United Resin
Look to United Resin as a trusted source of epoxy resin systems. We have an extensive portfolio of products for potting, encapsulating, and casting electronic components. They offer excellent thermal management, as well as excellent adhesion to various substrates, including PTFE, nylon, acetal, ceramics, and stainless steel. All our materials are non-hazardous, REACH/RoHS compliant, and solvent-free.
With over 50 years of industry expertise, we are dedicated to creating epoxy resin formulations that meet your unique requirements. Experience consistent quality and performance in every application with our wide portfolio of products, our ability to create customized solutions for our customers’ needs, and our trusted manufacturing processes.
Contact us to find the solution for your thermal management needs, or request a quote today.
The information presented herein is intended for general background and informational purposes only and not as advice about any product, application, or process. We encourage you to contact us for information concerning your specific needs and requirements and to discover how United Resin may assist you.