Oct 19 – 22, 2011
Hotel Roanoke, Roanoke VA
US/Eastern timezone

Negative coefficient of thermal expansion in (epoxy resin)/(zirconium tungstate) nanocomposites

Oct 22, 2011, 11:09 AM
12m
Crystal Ballroom C (Hotel Roanoke, Roanoke VA)

Crystal Ballroom C

Hotel Roanoke, Roanoke VA

Speaker

Erich See (Virginia Tech)

Description

The alpha-phase of zirconium tungstate (Zr W_2 O_8) has the remarkable property that its coefficient of thermal expansion (CTE) takes on a nearly constant negative value throughout its entire range of thermal stability (0 -- 1050 K). Composites of Zr W_2 O_8 nanoparticles and polymer resins have a reduced CTE compared to the pure polymer, but previous work has been restricted to measurements near room temperature. We show that the CTE of such composites can take on increasingly negative values as the temperature is lowered to cryogenic values. We used this phenomenon to fabricate a metal-free all-optical cryogenic temperature sensor by coating a fiber optic Bragg grating with the nanocomposite. This sensor has a sensitivity at 2 K that is at least six time better than any previous fiber-optic temperature sensor at this temperature.

Co-authors

Gianluigi Ciovati (Jefferson Lab) Dr Hans Robinson (Virginia Tech) Lauren Neely (MicroXact, Inc.) Madrakhim Zayetnikov (MicroXact, Inc.) Vladimir Kochergin (MicroXact, Inc.)

Presentation materials