In this article, Qpedia will explore some innovative thermal management products that have recently hit the market. These new thermal products encompass a variety of thermal management applications from CPU coolers to thermal interface materials (TIM) to sensors and test instruments to advanced materials and concepts.
One Part, Silver Conductive Epoxy
Silver filled epoxy adhesive system Master Bond EP3HTSDA-2 was developed for crucial thermal management applications. As a one component system, it is not premixed and frozen and has a very long working life at room temperature. This compound possesses a high thermal conductivity of 45-49 BTU•in/ft2•hr•°F [6.5-7.0 W/(m•K)].
It can be applied in ultra-thin bond lines and contains particles with an average size of 2-3 microns. EP3HTSDA-2 exhibits very low thermal resistance of 2-3 x 10 -6 K•m2/W. It also has outstanding electrical conductivity with a volume resistivity less than 0.001 ohm-cm. EP3HTSDA-2 meets NASA low outgassing specifications and is serviceable from -80°F to +450°F [-62°C to +232°C].
This product adheres well to similar/dissimilar substrates such as aluminum, ceramic, copper, fiberglass, polyimide and silicone die. This formulation is designed to cure in 20-30 minutes at 250°F or 5-10 minutes at 300°F. Die shear strength has a 20-20 Kg-f value at 75°F measured for a die size of 2×2 mm [80×80 mil]. EP3HTSDA-2 is packaged in syringes or glass jars. Common sizes range from 20 grams, 50 grams, 100 grams to one and multiple pound units.
For storage simple refrigeration is recommended. Shelf life is a minimum of 3 months in original unopened syringes or jars.
Portable AC Keeps Computer Systems Cool
Tripp Lite’s SRCOOL12K is a new-generation air conditioner designed for supplemental area cooling, emergency cooling and off-hour cooling applications. Efficient, compact, self-contained and portable, the 120V, 60 Hz SRCOOL12K is ideal for use in data centers, server and wiring closets, IT environments, home and small business offices, conference rooms, warehouses, entertainment centers or other venues with heat-sensitive equipment, particularly in areas that facility air conditioning can’t reach.
The SRCOOL12K not only adjusts ambient room temperatures, but can also dehumidify and filter the air, providing better air quality for enhanced equipment performance with minimal noise and power consumption. The SRCOOL12K uses environmentally friendly R410a Freon, which complies with EPA standards for 2010 and beyond, and is accepted worldwide. Designed for quick, simple installation, the SRCOOL12K plugs into a standard 5-15R outlet with no adapter required.
Both a standard louvered vent (for general room cooling) and a directional ducted cooling vent (to direct cold air where most needed) are provided. A directional exhaust duct safely removes hot air from the room. The built-in dehumidifier expels condensed water through the exhaust duct, with no need for a drain tube, drain pan or water collection tank. The SRCOOL12K meets the needs of the most demanding applications with 12,000 BTU of cooling power.
A built-in timer enables the unit to be programmed for unattended startup and shutdown. Controls and displays are conveniently mounted on the top panel. An included window/drop ceiling kit provides multiple installation options.
Technology Enables Thin, Safe, Heated Garments
DuPont Advanced Materials (DuPont) today announced the newest offering from DuPont™ Intexar – a powered smart clothing technology for on-body heating. Intexar Heat is a thin lightweight and durable heating solution for outdoor clothing that is designed to be easily integrated into garments. Intexar Heat is a revolutionary stretchable ink and film that when powered, creates a comfortable warmth.
The heater that feels like fabric, doesn’t rely on cables, thick wires or big batteries, and can stand up to very cold environments. From outdoor enthusiasts to industrial workers, Intexar Heat can help conquer the elements in comfort, increasing focus and improving performance. Intexar materials also can enable biometric monitoring in smart clothing.
Pulse rate, respiratory rate, muscle activity and form awareness are all measurable using sensors and conductive pathways built from Intexar.
Heat Shield Technology Protects EV Batteries
Freudenberg-NOK Sealing Technologies has produced a light weight, low volume silicone rubber heat shield for lithium battery systems. The product was developed in response to trends with original equipment manufacturers for battery systems that will increase the driving range for electric vehicles. OEMs have found ways to increase the energy density inside battery cells, packing more chemical energy in the same cell volume. Individual cells also are stored tightly together to maximize the energy density of the system.
Today’s battery systems need to support ultra-fast charging, with OEMs looking for a complete system charge within 10-15 minutes. This pushes a high amount of energy into the system, creating a safety issue with thermal management. Placing heat shields between the cells, would keep heat from transferring from one cell to another in the case of a thermal event. Freudenberg developed a heat shield based on a silicone rubber that remains flexible under heat and adjusts to changing size of a cell during charging or over its lifetime.
The critical issue is to block the heat, which is caused by the cell in a thermal runaway state. Typical values are 600°C at the surface of the housing for some 30 seconds. The goal was to create a heat shield that could withstand those parameters while maintaining a temperature of 200°C or below.
The silicone rubber heat shield is made with a waffle structure that creates air pockets between the shield and the cell, as well as limits the amount of direct contact area between the shield and the cell surface.
Gap Filler Transfers Heat and Absorbs EM Waves
Fujipoly has introduced a new thermal interface material that also absorbs a wide range of unwanted electromagnetic energy. The tacky, gel-like consistency of Sarcon EGR-11F makes it easy to handle and apply without requiring additional adhesive. When placed on top of a heat source such as an IC chip, the compliant material fills any unwanted air gaps allowing for more efficient transfer of heat to nearby components or heat sinks.
Sarcon EGR-11F also provides excellent shielding effectiveness across a broad frequency spectrum while exhibiting a thermal conductivity of 1.0 W/m°K (ASTM D 2326) and a thermal resistance of 1.05°Cin2/W at 14.5 PSI. This highly versatile material is available in three sheet thicknesses (0.5, 1.0, 1.5mm) up to a maximum dimension of 300mm x 200mm. Sarcon EGR-11F can also be ordered in die-cut form to fit almost any application shape.
The material is well-suited for environments with operating temperatures that range from -30 to +120°C and exhibits a UL94 flame retardant rating of V-0.
High Performance IR Sensor Uses MEMS Technology
The D6T-1A-02 from Omron is the latest in sensory innovation with super-sensitive, infra-red (IR), non-contact temperature sensing capabilities using MEMS technology. The D6T thermal sensor is ideal for building automation applications, measuring the temperature in a room, or detecting occupancy, even when people are stationary.
Additionally, because the D6T is fully non-contact it offers a wider detection range, as well as ultra-sensitive heat sensors – an excellent alternative to PIR detectors and pyroelectric sensors. Making full use of MEMS technology, the D6T provides the ability to measure surface temps anywhere between -40° to 80°C (-40°-176°F) with an accuracy of +/- 1.5°C, and resolution of 0.06°.
The new sensor combines state-of-the-art MEMS thermopile, a sensor ASIC (Application Specific Integrated Circuit), and a signal processing microprocessor in a 12.0mm x 11.6mm x 9.2mm package. Its narrow field of view at 26.52 allows for accurate readings of a specific object within range.
For more information about Advanced Thermal Solutions, Inc. (ATS) thermal management consulting and design services, visit https://www.qats.com/consulting or contact ATS at 781.769.2800 or ats-hq@qats.com. To register for Qpedia and to get access to its archives, visit https://www.qats.com/Qpedia-Thermal-eMagazine.