Chromium nitride/titanium-titanium carbonitride multilayers composed of a 40 nm Cr interface followed by a 4.4 mu m thick Cr2N layer, a 150 nm thick Ti layer, and a 1 mu m thick TiCxNy top layer were deposited on silicon wafers by magnetron sputtering. The structural changes and the phase content changes of these multilayer samples were studied bymeans of high-temperature in-situ X-ray diffraction experiments at temperatures up to 550 degrees C. The lattice constants of the Cr phase as well as the Ti phase display an aberrant expansion behaviour during these experiments which is influenced by the defect structure, a nitrogen incorporation, and residual stress in the layers. The results were comparedwith structural data obtained by ex-situ transmission electron microscopy investigations of pristine and heated material, revealing phase separation and strong diffusion phenomena. (C) 2014 Published by Elsevier B.V.