The Development of a Dilute Aluminum-Gold Alloy for Thermal and Resonance Neutron Flux Measurements

Aluminum-gold alloy wire of very uniform cross section and composition has been made for the preparation of neutron flux monitors. Because the wire is uniform, a device to cut it into pieces of equal length can be used for the rapid preparation of flux monitors and the need to weigh individual monitors can thus be avoided. Homogeneity of composition was achieved mainly by rolling and annealing, and the effectiveness of each step was assessed by neutron-activation analysis. The gold content of the final product (wire 0.018 in. diameter) was also determined by activation analysis and was found to be 0.0985 ± 0.0020 atom %. Thermal-neutron self-shielding in this wire is negligible and cadmium ratio experiments show that resonance-neutron self-shielding amounts to about 2.5%.