Mission Statement

Understanding engineering and functional materials behavior under complex environments.

Instrument Description

VULCAN is designed for deformation, phase transformation, residual stress, texture, and microstructure studies. Load frames, furnaces, battery chargers, and other auxiliary equipment for in situ and time-resolved measurements are integrated in the instrument. As a time-of-flight diffractometer at the world's most intense pulsed, accelerator-based neutron source, VULCAN provides rapid volumetric mapping with a sampling volume of 2-600 mm3 and a measurement time of minutes for common engineering materials. In extreme cases, VULCAN has the ability to study kinetic behaviors in sub-second time frames.

Applications

VULCAN covers a broad range of applications in materials science and engineering, from residual stress determination in engineering components to understanding the fundamental aspects of material behaviors during synthesis, processing, and service. Research areas that can benefit of VULCAN include but are not limited to the following:

  • In situ studies of materials behavior during processing or synthesis: phase formation, temperature distribution, texture changes, stress development, precipitation.
  • In situ loading studies of crystalline/amorphous materials at high temperatures: phase transformation, fatigue damage, creep behaviors, and other deformation mechanisms in nanostructured materials, piezoelectric and shape-memory alloys.
  • In situ/operando studies of working system such as batteries and hydrogen storage devices.
  • Nondestructive residual stress and microstructure investigation in engineering components.

Specifications

Selectable chopper speed and bandwidth:60 Hz, 1.44 Å; 30 Hz, 2.88 Å; 20 Hz, 4.32 Å ( for measurable d range in 90 degree detectors, divide the bandwidth by 1.414)
Sample stage:Rotation: 360°, X,Y, +/-250 mm, Z +/-300 mm. Weight capacity: 2000 kg. Positional precision: < 25 μm for loads < 200 kg; 100 μm for loads between 200 and 2,000 kg
Detector:+/-90 position-sensitive detectors (3 modules each side), measures two orthogonal strain components simultaneously
High-intensity and high-resolution exchangeableguides:~0.45% (HI) and ~0.25% (HR) Δ-d/d resolution
Beam size2-10 mm horizontal and 2-12 mm vertical incident slit. 2 mm and 5 mm receiving radial collimators

Various sample environments enable in situ diffraction measurement (see SNS sample environment page for details).