Revolutionize athermalization with ALLVAR Alloys, the only Negative Thermal Expansion Metals in the World.

Athermal Optics.

With ALLVAR Alloy 30, passive athermal optics are no longer dictated by the coefficient of thermal expansion of housing materials. Negative thermal expansion lens barrels or standoffs between lens and housing materials can be made to match the thermal defocus caused by an individual lens or the entire lens stack. Smaller, lighter, passive athermalization can reduce design time, scrap, and length of your system. 

Ultra-Stable Struts.

Negative Thermal Expansion ALLVAR Alloys can compensate for the expansion and contraction of other materials. ALLVAR Alloy 30 struts can be designed for telescopes and high precision scientific equipment. The strut shown to the right was designed with ALLVAR Alloy 30, titanium 6-4, and invar and has a 0.6ppm/°C CTE at room temperature. 

Athermalization enabled with Negative Thermal Expansion.

The process of removing thermal effects from a system is called athermalization. Creating an athermal design that actively athermalizes a system is challenging, and often increases the weight and complexity of the system. Passive athermalization achieves the same results as an active system, but without using powered systems or requiring outside feedback. It requires iterative changes and tweaks to hone the thermal changes of individual components in a design, so that they together work in unison independent of thermal effects. These systems are challenging to design, manufacture, and test. ALLVAR Alloys make this process much easier. 

Targeted Thermal Expansion.

Negative thermal expansion ALLVAR Alloys allow engineers and designers to target a specific thermal expansion for their system. Designers select a specific thermal expansion, from –30 ppm/°C to a joined materials positive coefficient of thermal expansion, and incorporate a calculated length of ALLVAR Alloy 30 to hone in on a target CTE. Being able to tailor a specific CTE flips the design paradigm on its head. 

Thermally stable bolted joints. 

Bolting dissimilar materials can lead to variable thermal loading, increased fatigue, and possibly joint failure. ALLVAR Negative CTE washers offer a simple solution to keep clamping force-loads constant.


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Video Resources - Learn More About ALLVAR and Negative Thermal Expansion

Click the images below to get our selection of videos and learn more about our company, our technology and our products.

ALLVAR University

Watch our videos to learn more about negative CTE and how it can be precisely compensate positive CTE components in athermal assemblies.

Demonstration Videos

Our demonstration videos show how important a washer can be, and how a simple change in Optics can eliminate thermal focus shift.

Meet Our Team

Meet our team, from our founder to our engineers, and hear their perspective on their new negative CTE alloys.

Watch a Webinar

Interested in a longer lesson on negative CTE and ALLVAR Alloys? Watch our webinar to get the details.

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