In situ neutron diffraction measurement of transient temperature and stress fields in a thin plate

Separating the elastic and thermal strains has been a long standing problem for in situ neutron diffraction measurement of transient temperature and stress fields. Using the plane stress condition, we demonstrate a method to decompose the thermal and elastic strains from the measured lattice spacing changes. The method was validated using a thin plate subjected to a local moving heat source. The methodology developed herein has practical applications for a variety of materials processing technologies such as welding, forming, and heat treatment. © 2006 American Institute of Physics.