3D printed spherical environmental chamber for neutron reflectometry and grazing-incidence small-angle neutron scattering experiments

Abstract

In neutron scattering on soft matter, an important concern is the control and stability of environmental conditions surrounding the sample. Complex sample environment setups are often expensive to fabricate or simply not achievable by conventional workshop manufacturing. We make use of state-of-the-art 3D metal-printing technology to realize a sample environment for large sample sizes, optimized for investigations on thin film samples with neutron reflectometry (NR) and grazing-incidence small-angle neutron scattering (GISANS). With the flexibility and freedom of design given by 3D metal-printing, a spherical chamber with fluidic channels inside its walls is printed from an AlSi10Mg powder via selective laser melting (SLM). The thin channels ensure a homogeneous heating of the sample environment from all directions and allow for quick temperature switches in well-equilibrated atmospheres. In order to optimize the channel layout, flow simulations were carried out and verified in temperature switching tests. The spherical, edgeless design aids the prevention of condensation inside the chamber in case of high humidity conditions. The large volume of the sample chamber allows for high flexibility in sample size and geometry. While a small-angle neutron scattering (SANS) measurement through the chamber walls reveals a strong isotropic scattering signal resulting from the evenly orientated granular structure introduced by SLM, a second SANS measurement through the windows shows no additional background originating from the chamber. Exemplary GISANS and NR measurements in time-of-flight mode are shown to prove that the chamber provides a stable, background free sample environment for the investigation of thin films.

PMMA-b-PNIPAM Thin Films Display Cononsolvency-Driven Response in Mixed Water/Methanol Vapors

“…For all SR and ToF-NR measurements, a sample environment, which was three-dimensional (3D) printed from an AlMgSi alloy, was used . It features aluminum windows and liquid channels inside the walls and lid to achieve a homogeneous temperature at the sample position.…”

Flexible Sample Environment for the Investigation of Soft Matter at the European Spallation Source: Part II—The GISANS Setup

“…This ensures that the 3D printed material is not hit by the incident nor the scattered neutron beam (which would produce unnecessary background). It was shown with the previous chamber design that the 3D printed material yields a strong scattering signal when directly hit, but it generates no detectable background otherwise [43,45,46]. As such, NR and GISANS measurements with no measurable background contribution from the chamber itself were already demonstrated.…”

“…We designed a spherical 3D-printed humidity metal chamber that provides precise control over temperature and, in conjunction with the gas flow assembly, humidity while offering a relatively large volume that can accommodate large samples and additional, interchangeable equipment. It is an upgraded version of a previous design of ours, with an improved control over environmental parameters and an easier general handling of the chamber [43]. The spherical design depicted in Figure 1 enables a homogeneous heat distribution for isothermal and temperature switching experiments while simultaneously preventing condensation due to the lack of sharp edges and corners, which are usually critical points for condensation [44].…”

“…The windows are covered by a 0.1 mm aluminum foil clamped against the windows by a 2-mm-thick aluminum counterpart. For further details on the sample holder and the various connections to the chamber, we refer to our previous publication [43].…”

Ternary Nanoswitches Realized with Multiresponsive PMMA‐b‐PNIPMAM Films in Mixed Water/Acetone Vapor Atmospheres

“…ToF‐NR and SR : All ToF‐NR/SR measurements were carried out using a specialized sample environment featuring aluminum windows and liquid channels inside the walls and lid to ensure a homogeneous temperature. [ 68 ] ToF‐NR measurements were carried out at the horizontal neutron reflectometer REFSANS at the Heinz Maier‐Leibnitz Zentrum (MLZ) in Garching, Germany. [ 69 ] Specular reflectivity data were analyzed using the Motofit plugin [ 70 ] for IGOR PRO v7.08 (WaveMetrics, Portland, U.S.A.), to yield the thin‐film SLD profiles along the surface normal z .…”