Unalloyed chromium and chromium containing approximately 3 wt pct ThO2 (2.2 vol pct) were prepared from powder produced by a chemical vapor deposition process. When rolled to sheet and tested in tension it was found that the thoriated material had a lower ductile-to-brittle transition temperature (DBTT) than unalloyed chromium. This ductilizing was evident both in the as-rolled condition and after the materials had been annealed for 1 hour at 1200°. The DBTT values were: Open image in new window The improved ductility in thoriated chromium may be associated with several possible mechanisms: 1) particles may disperse slip, such that critical stress or strain concentrations for crack nucleation are more difficult to achieve; 2) particles may act as dislocation sources, thus providing mobile dislocations in this normally source-poor material, in a manner similar to prestraining; and 3) particles in grain boundaries may help to transmit slip across the boundaries, thus relieving stress concentrations and inhibiting crack nucleation.