Design of Radial Collimator of Neutron Diffractometer for Residual Stress and Defect in Material and Component

The gauge principle of the radial collimator in real space and phase space was analyzed to design the radial collimator of the neutron diffractometer for residual stress and defect in material and component in order to set the gauge volume in large engineering component at far distance. The analytical formulas and simulations were introduced to calculate the gauge volume of the radial collimator. The nylon wire with diameter of 0.2 mm was used to test the gauge volume of the radial collimator at E3 instrument, Germany. According to the experimental result, the JRR3 analytical formula was chosen to design the gauge volume of the radial collimator. The effect of the parameters on gauge volume and transmission efficiency was studied systematically. Finally, the radial collimators with gauge volume were designed in combination of the spatial geometrical layout with the parameters of 1, 2, 3, 4 and 5 mm.