STRESS-SPEC

• Industrial components
• Welds
• Superalloys
• Strain mapping
• Surface measurements from 150 µm possible [2]

• Global textures
• Local textures
• Strain pole figures
• FHWM pole figures

• Phase transformation dynamics
• Spatially resolved phase analysis (e.g. batteries)

[1] Hofmann, M. et al., Physica B, 385 386, 1035 1037 (2006).
[2] Saroun, J. et al., J. Appl. Cryst., 46, 628 638 (2013).
[3] Brokmeier, H.-G. et al., Nucl. Instr. Meth. A, 642, 1, 87 92 (2011).

• XYZ-table
  • capacity 300 kg, travel xy = ±120 mm, z = 300 mm, accuracy ~ 10 µm
• Load frame
  • +/- 50 kN, heatable to 1000°C (in air), rotabale
  • +/- 100 kN, heatable to 1500°C (vacuum)
• Full circle Eulerian cradle (max. load 5 kg)
• ¼ circle Eulerian cradle for heavy samples
• Standard sample environment (e.g. furnace, cryostat)
• Quenching & deformation dilatometer

A positioning system consisting of a Stäubli-6-axes robotic arm for texture and strain measurements (payload up to 30 kg) can be mounted instead of the standard sample table. It offers more flexibility than an Eulerian cradle and can be also used as automatic sample changer for texture measurements [4].

[4] Randau, C. et al., Nucl. Instr. Meth. A, 794, 67–75 (2015).

• SR-3 thermal neutrons
• Collimators (‘in-pile’) 15’, 25’, open

• Ge(511), Si(400), PG(002)
• 2θ_M 35° – 110° continuous
• Wavelength 1 Å – 2.4 Å ; (2.5 Å^-1 < Q < 10.5 Å^-1)

• Primary slit: automatic continously variable up to 7 × 17 mm² (W x H)
• Secondary slit: continuously variable up to 15 mm
• Radial collimators (FOV = 0.5 mm, 1 mm, 2 mm, 5 mm, 10 mm)

• Primary slit: max. 30 × 40 mm² (W x H)
• Secondary slit: continuously variable up to 15 mm or open

• ³He-PSD, 25 × 25 cm²; 256 × 256 pixels

STeCa [5]
STeCa is the standard software tool to analyse the 2D-detcetor data of STRESS-SPEC. Besides display functionalities, various functions for integration and Bragg peak refinement are available. In addition, one can generate and visualise the pole figures from texture measurements. The software is available for Linux or Windows and can be downloaded from the web page of the Computing Group

DISEMM (Diffraction assisted mechanical modeling) [6]
The software DISEMM is designed to analyse diffraction data from in-situ loading experiments to obtain diffraction elastic constants and single-crystal elastic constants as well as to describe the mechanical behavior by the elasto-plastic self –consistent modeling. DISEMM offers a variety of grain-to-grain interaction models, integrates texture and multi-phase alloys. The software is currently available for Windows. The DISEMM software can be downloaded here, with the corresponding manual here.

STRESSFIT [7,8]
is a Python package for fitting of neutron residual strain scanning data. The primary objective is to restore intrinsic lattice strain distributions measured by neutron diffraction. In an experiment, this distribution is smeared by finite spatial resolution of the instrument. Measured strains are also affected by so-called pseudo-strains, which arise in general from inhomogeneous sampling of the material. The best known is the surface effect, which occurs when the nominal gauge volume of the instrument is only partly immersed under the sample surface. This gives rise to peak shifts (pseudo strains) of similar magnitude as the intrinsic strain. The Python package can be reached here (https://github.com/NPLtools/stressfit), as well as the respective available documentation.

[5] Randau, C. et al., J. Appl. Cryst., 44, 641-646 (2011)
[6] Heldmann, A. et al., J. Appl. Cryst., 52, 1144-1156 (2019)
[7] Rebelo Kornmeier, J. et al., Materials Characterization, 154, 53-60
[8] Šaroun, J. et al., Physica B: Condensed Matter, 551, 468-471