Page 87 - ILL Annual Report 2019

MODERNISATION PROGRAMMES AND TECHNICAL DEVELOPMENTS
84-85
Figure 1
Photo taken during the assembly of a sample stick. The bellows are welded to the inner tube and the capillaries are assembled together before insertion.
Cu tube hosting the Pt100 sensor
tube of the inner chamber
700 MPa capillary
capillary hosting capillary hosting the
the heater
sample wiring
bellows to accomodate dilatation
The high-pressure cells used for neutron experiments have to withstand huge forces without absorbing too many neutrons. We have therefore also designed and produced several high-pressure cells using different materials. These include the titanium null-matrix alloy (Ti) and zirconium (Zr), which provide a total coherent scattering length equal to zero; and the fully hardened CuBe2 alloy, which can be employed at temperatures of up to 300 °C for pressures lower than 700 MPa (figure 2). These cells can be combined with Al inserts equipped with rectangular slits. These in turn can host lipid membrane layers deposited
on silicon wafers to model biological membranes, for instance. The wafers are surrounded by water and thus protected from breakage, permitting in situ studies of membrane layers under high pressure and high temperature conditions.
Acknowledgments
We gratefully acknowledge the CNRS – Défi Instrumentation aux Limites 2014 – for financing the development of the high-pressure cell.
Figure 2
Photo of the 250 and 600 MPa TiZr cells, the 700 MPa CuBe2 cell, Al inserts and sealing components.
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