Australian researchers have synthesized a material with the most stable thermal stability ever. A discovery that could find application in space rockets, aircraft engines or medical implants.
Australian scientists have created the most thermally stable material yet discovered. Made of, aluminum, and d’ , son Remains approximately the same from 4 to 1,000 degrees (-269 to +1,126 °C), that is, an amplitude of about 1,400 °C!
vast majority of content, due to the thermal movement of atoms. think for example I’m going up . Thus the coefficient of each material is Thermal, calculated in Kelvin. 1 cm piece of aluminum3 For example 0.075 mm. from “inflate”3 for an increase of 100 °C, while 1 cm3 water 0.21 cm. will take3 When heated to 100 °C (thermal expansion due to It is also the main reason for the rise of the oceans).
Rockets that have to withstand extreme temperature variations
All this is very annoying in some applications where the material is very strong. for example are exposed to intense cold in space and a During takeoff and landing. Similarly, the Lockheed SR-71 Blackbird spy plane runway was known to spray with fuel at ground temperature, as the fuel tanks were not completely sealed until they overheated during flight. We can also cite Medical devices, which, even when subjected to low thermal dimensions, should not vary in volume at all. en general, Thermal damage eventually damages the material and can cause many problems.
So for many years, scientists have been looking for “materials with zero thermal expansion” (zero thermal expansion, ZTE), the amount of which does not change with temperature. Zerodur, a composite inwhich has a nearly zero coefficient of expansion over a thermal range between 20 and 320 °C, is used for example from Like VLT in Chile.
an exceptionally low coefficient of thermal expansion
Yet it was coincidental that Neeraj Sharma’s team at the University of New South Wales discovered their new material, ZTe, described in the journal.. « We were conducting experiments for battery-based research, and we were surprised to see the thermal property of this particular structure. », . Ingredients, Exact Formula Sc. with1.5Ali0.5woo3hey12, αv = −6 × 10 . is the thermal expansion coefficient of-8 K-1. This means that 1 cm. A piece of3 Only 0.003 mm in volume. will lack3 For a temperature rise of 100 °C! This exceptionally low coefficient can be measured very precisely thanks to the powder diffractometer ofAustralian Organization for Nuclear Science and Technology (ANSTO), which can detect very small deviations.
Optimum rearrangement of atomic bonds
But how to interpret this incredible? « The bond lengths, angles, and positions of the oxygen atoms interact with each other to preserve the total volume. », suggests Neeraj Sharma. In other words, temperature variation produces changes at the molecular level but which do not affect the overall sample size. The role of other compounds is less clear, and will require further investigation.
« Science1.5Ali0.5woo3hey12 can be easily synthesized on a large scaleReassure Neeraj Sharma. and its components such as tungsten oxide andare relatively inexpensive. Hence it can be manufactured on a large scale and at a low cost. ».