Transfer Heat with Thermal Interface Materials
Thermal Interface Material or TIMs, are materials used in the transferring of heat within electric assemblies. Thermal management is essential in ensuring the safety of your electronics.
Not only can overheating cause a fire hazard, but it can also cause the device to not perform as well, or even stop working altogether. Thermal Interface Materials are inserted between two components in order to enhance the thermal coupling between them.
At Materials Direct we offer a wide range of high-quality Thermal Interface Materials, custom cut to your specifications.
Sourcing and Installing Thermal Interface Materials Correctly
Some TIMs have an adhesive layer that assists assembly, making the installation of your thermal interface materials simple and easy to apply.
Not all TIMs need electrical Isolation and therefore a generally lower cost material can be used such as graphite. Our online store offers a wide range of TIMs, making it easy and convenient to find what you’re looking for.
Custom Cut Materials
Materials Direct is approaching this market in a way that is easy to order and specify in Electronics across all industries. Customers who need a certain brand of material that does not appear on the site can apply for us to add this stock to the site’s portfolio based on potential usage.
No Tooling Charge
There is NEVER a tooling charge for manufacturing
Parts made & shipped worldwide in as little as 24 hours
Technical expertise available from our specialists
100% Payment Secure
We ensure secure payment with a wide array of options
Instant Quotes – Purchasing Made Easy
The main problem for design engineers and purchasing has been until now the quick supply of parts as often the custom pad is one of the last items to be specified in the design of an Electronic assembly.
Materials Direct not only provides an instant quote but gives the buyer the offer of uploading their custom design for it to be manufactured within 24hours if the material is in stock.
Get an online quote
for the part / gasket
Upload your design
Place and pay
for your order
Parts dispatched to you
in as little as 24 hours.
What Do TIMs Consist Of?
Thermal Interface Materials are used to greatly reduce the interfacial microscopic air voids found on the surfaces of hot components and heat sinks in electronic assemblies. Removing the air from the interface greatly improves the heat transfer from the hot device to its heatsink.
They will usually consist of a Carrier such as a Glass Fibre Cloth or Polymer. This carrier will then have a coating or binder that is mixed with a non electrically conductive ceramic to form a fabric-like material.
The fabric-like material (TIM) can then be converted into bespoke parts or shapes which are then placed between the heat-generating component and the heat sink/spreader to cool it.
Phase Change Materials
The majority of TIMs need mechanical pressure in order for them to reduce the micro-air voids by the soft binder/ceramic “cold-flowing or bedding” into the irregularities on the surfaces.
However, there is a range of TIMs which do not need pressure and instead use heat to soften the material so that they naturally flow into the micro-voids. The name for these materials is Phase Change, as they move from solid towards liquid but never get that far; they only soften within a temperate range.
These Phase change materials are particularly important if the devices cannot have high pressures applied to them such as CPUs in a computer application or a LED Chip On Board device.
Thermal Interface Materials to Suit Many Applications
TIM’s can be supplied as thick Gap filling pads above 0.5mm to 6mm in 0.5mm increments. These products interestingly do not need high pressure to make them flow as they are designed to be naturally tacky thereby removing the micro-air voids. The also often have the advantage of absorbing vibration in automotive or portable applications.
The softness of the TIMs is important for other reasons such as coefficient of thermal expansion as over the normal use of the electronic assembly the devices have differing rates of thermal expansion and this expansion needs to be accommodated.
At Materials Direct parts are converted from sheet or roll materials and can be supplied as single parts, multiple parts on a sheet, or even die-cut on a roll. TIMs deliver a number of different functions including Electrical Isolation, Conductive heat transfer, and softness to help exclude micro-air voids at the mating surfaces.
We Provide Thermal Interface Materials from Trusted Brands
At Materials Direct we only sell Thermal Interface Materials from trusted brands and ensure our products are of the highest quality for our clients.
Very fast reply, very good order following and delivery in 24H. to recap a verry good experience with Materials Direct for a verry urgent need. I recommend a lot.
'Having the ability to be supplied with precision cut materials for prototypes within 2 days has been excellent!’
'We have the need for small to medium batch sizes of various technical materials and Materials Direct have been highly responsive to our urgent needs'
‘We have had to change our designs in the development stages three times. Materials Direct did not charge for these changes as the sizes stayed the same. Excellent!’
‘Precision and high quality of parts received have been consistently to a high standard.’
'Buying online with Materials Direct has proven to be more efficient in time and deliveries, especially when scheduling future orders.’
Frequently Asked Questions
What is Thermal Grease?
Thermal grease has been around since the early days of manufacturing electronics and trying to control the unwanted heat that is built up in the components. Thermal grease is applied between 2 surfaces where heat needs to be transferred between the hot component and its heatsink or heat spreader. It works by removing air voids present microscopically on the mating surfaces. Air has a very poor thermal conductivity and will greatly reduce the thermal transfer if it is present within the interface.
How do Thermal Pads work?
Pads provide a flexible method of thermally joining 2 mating surfaces and often delivering electrical isolation also. Also materials such as Bondline can also mechanically bond as well. They remove air voids as they are able to flow.
Why do I need thermal management?
Thermal management is vital to the performance and safety of your assembly. A simple 10C rise in temperature within your semiconductor has been said to half its operating life. 10 Degrees C change in temperature can happen with a day/night temperature excursion. In the case of an LED, it is the same plus the light outputs are greatly reduced and even the colour of the light can be altered with heat build-up. If you manage your heat you can often drive the components harder achieving greater efficiencies and even reducing the cost of your application. For instance, you may be able to reduce your component count thereby making very big savings. Also, smaller heat sinks can be possible just by choosing a greater performing Thermal interface material.
Do I need to apply pressure to make the TIM work?
Traditional Thermal Interface materials often work by means of the material “cold flowing” and removing or reducing the micro air voids. To get this to happen the material must have mechanical pressure applied by means of a fixing method (commonly screws or clips).
A more recent material (last 10 years or so) called “Phase Change” can be used on pressure-sensitive applications such as ceramic or CPU type applications. The material softens when it reaches a threshold temperature typically 55-60C to “wet-out” the surfaces to remove micro-air voids. The material only has to see this temperature once and then it is bedded in. In the case of Gap Pads (pads thicker than 0.5mm thickness) then the surfaces are often visco-elastic and have a residual stickiness to them which means they are “auto-flowing” without a great deal of pressure. The material feels sticky because it is “flowing” into your finger print making it feel tacky but there is NO adhesive present!
How do I install thermal pads?
Most thermal interfaces are simply applied by assembling them between mating surfaces and clamping. Others such as Bondline are thermal conductive double-sided tapes. Gap pads are again designed to be installed between mating surfaces with mechanical fixings. It can be a good idea sometimes if the pad is thin to make either a visual tab to protrude so that it can be seen by the assembly operative or inspection department as this will indicate the presence of the TIM. (Sometimes they are missed out of the assembly and cannot be see because they are too thin leading to latent failures in the field).
What if I don’t want to apply pressure to my delicate electronic component such as a CPU?
You can select a phase change or soft gap pad instead of a TIM needing higher pressures.
Do I need to replace my thermal pads?
If you need to replace a TIM perhaps for servicing or warranty then ideally you should see material on both surfaces as you part them. This means the “wet out” has happened well and thermally you are getting the best performance. Surfaces should be cleaned down and a new TIm should be applied.
Are thermal pads needed in Electric Vehicle applications?
TIM’s are required wherever there is a need to manage the unwanted heat building up in any electronic assembly. A very common application for Materials Direct is Electric vehicle battery systems. Fast charging and fast discharging lead to very high temperatures needing to be controlled often with liquid cooling plates. Those plates need to be connected to the cells via conductive paths being the most efficient. There are also often very high voltages and currents in these systems so high-reliability materials are required.
What materials are thermal pads made of?
A typical TIM consists of a “carrier” which can be a glass fibre fabric or polymer to which a “binder” is coated to both sides. The “binder” has in it a blend of ceramic particles called the “filler”. The assembled TIM is often soft to aid “cold Flow” when under pressure to “wet-out” the surfaces and remove micro-air voids. Some TIM’s are however a homogenized material and consist of “binder” and “filler” only such as UniGap products. Bondline tapes also are Acrylic adhesive and filler only without a carrier.
How does thermal adhesive tape work?
The double-sided adhesive tapes such as 3M and Bondline are some of the highest thermal conductive tapes available on the market. The bond with high strength electrically isolates and thermally conducts. They remove the need for unsightly screws and fixings in LED lighting applications. Ideal for use with bonding Aluminium backed PCBs or FR4 PCBs to metal heat sinks. However, they should not be used on powder coated surfaces.
Supplying Technical Materials
To a Range of Sectors
Each sector has its own unique requirements and specifications. Materials Direct works to ensure that each sector we supply to, receives the highest quality and best-performing products in relation to their industry and specific need.
The Aerospace industry demands the highest performing, most reliable technical materials to protect their electronic assemblies.
Automotive / EV
Automotive applications range from Engine management systems to motor drive controllers and custom-made gaskets and pads.
Industrial electronics are robust, have long lifetimes, are cost-sensitive, and suitable for use within difficult environments.
Sufficient thermal management in LED lighting can preserve longevity, increase reliability and optimise performance.
Materials used in military applications need to be of the highest quality and performance, often very rugged to very exacting standards.
Coupling discreet heat-generating semiconductors to heatsinks remains commonplace in power supply assemblies.