Specialist Castings is delighted to have been involved in an exciting project creating Invar parts for WEAVE (WHT Enhanced Area Velocity Explorer), a new multi-object survey spectrograph being constructed for the William Herschel Telescope (WHT) in the Canary Islands.

We created Invar parts for the WEAVE, a spectrograph that will allow astronomers to understand the Milky Way in greater detailThe spectrograph is an instrument that splits light into wavelengths to make it possible for astronomers to record and analyse and requires a high level of precision to ensure accuracy of results.

The new spectrograph will allow astronomers to take a spectra of up to 1000 stars and galaxies in a single exposure and marks a significant jump forward in the efficiency of the telescope (currently it is only possible to observe 100 objects simultaneously).

When completed, it’s hoped that the telescope will allow us to understand how the Milky Way was assembled by measuring the speeds of several millions of stars being mapped by the European Space Agency’s GAIA satellite.

As accuracy was so critical, we opted to cast parts using Invar, a nickel/iron composition alloy which is used where high dimensional stability is required.

Specialist cutting equipment is essential to complete Invar machining without having a detrimental effect on the material, and our expert team’s experience and equipment means we are perfectly placed to cast Invar parts to the most precise specification.

Why Invar?

Invar is ideal for components that require near constant dimensions as it is able to maintain its shape between temperatures of -100°C & 260°C without experiencing warping or thermal expansion.

Its unique qualities make it a popular choice for a range of applications where accuracy is key, including clock pendulums, measuring devices, aerospace engineering and the transportation of liquid natural gas due to the significant insulation it provides.

It is also a highly durable material, so it is perfect for precision instruments such as microscopes and telescopes.