ABSTRACT
Scanning and transmission electron microscopy have been used to investigate the reaction mechanism and microstructure of negative temperature coefficient, Ni1-xMn2+xO4 based thermistors. Evidence of unreacted NiO was found which contained florets of spinel with a cube//cube relationship to the rock salt matrix. In ferroelastically distorted samples, lamellar and herring bone domain structures were observed. Electron diffraction patterns from all samples examined exhibited streaking parallel to <110> directions which was associated with the appearance of sinusoidal, 10nm wide fringes in TEM images.
