Neutron diffraction analysis of a failed 1400s wrought iron tie rod from Milan Cathedral

We propose to deeply investigate one metallic (iron based) failed tie-rod sample, from Duomo di Milano (Italy). The tie-rod, a typical iron strengthening element in gothic cathedrals, dating back presumably to the 1410-1459 AD, presents an altered surface. In order to infer indications on the inner part too, with the benefit of a non-destructive technique, we plan to provide a neutron based characterization concerning the residual stress.This will allow us to infer important details on the production technologies and the conservation status, and moreover to address present-day structural integrity issues for the rods still in service in Duomo di Milano.