Figure 5
(a)–(e) Narrow-energy neutron transmission images of weld samples. Only neutrons in a narrow range of energy are used to form these images: (a) 1.09 ± 0.003 Å, (b) 1.14 ± 0.03 Å, (c) 1.57 ± 0.03 Å, (d) 1.72 ± 0.18 Å, (e) 1.84 ± 0.024 Å. Each of these images is normalized by the neutron transmission image (f) acquired past all Bragg edges (4.2–8 Å neutrons), where no diffraction is present in either of the steels or in copper. Image (f), shown not at the same scale, reveals the extent of the heat-affected zone within the steel plate. Strong texture is seen in the weld area with copper filler, where dark areas reveal the presence of preferred orientation leading to enhanced diffraction in that area. Some refraction at the Ti part of the weld is seen as a dark line around it. An animation representing a continuous scan through the narrow-band neutron images revealing the texture in the copper weld area can be found in the supporting information online (ks5507sup1.avi). |