The Prepared Of Doped Chromium Oxide Pigments And The Research On Its Spectral Properties

Infrared stealth is an important part of the stealth technology research. With the development of infrared detection technology, the higher requirements have been put forward for stealth performance of objectives. The development of multi-spectral infrared stealth materials has become a research focus. In addition, the rapid development and application of hyperspectral detection technology needs more accurate spectroscopy for stealth materials. Infrared stealth pigment is an important material for visible-near infrared stealth. The reflectance of pigment can be modified so that it could give the military the target surface and the natural background highly similar near-infrared reflectance properties. Thus, the difference of the characteristic of the target and background could be reduced. Hence, it is a new way to achieve near infrared stealth.Modified Cr2O3 is a common infrared stealth pigment, which can effectively achieve the target stealth in green vegetation environment. In this paper, the pigments were prepared by the solid state reaction method from the mixture of the relevant oxides, Cr2O3, TiO2 and Co2O3. The effect of process parameters on phase structure, particle size, and optical properties have been investigated by using X-ray diffraction(XRD), scanning electron microscope (SEM), Ultraviolet-visible spectroscopy(UV-vis) and CIE-L*a*b* colour measurements. The results show that the microstructure of the product has a significant effect on reflectance. Co2+ ion-implantation can influence the spectral reflectance of 550-700nm with the concentration increase of reflectance gradually reduced. In addition, the experiment also studied the influence of different process conditions on the crystal structure, the spectral reflectance and color properties.In addition, ZnO, MgO, NiO were doped into the compound respectively. The result shows that the introduction of Zn2+ ions improves red edge spectral reflectance of the powder, and can increase the brightness of the pigment. Prolonging of heat preservation time for powder did not affect reflectance in the visible band, but it can impact spectral reflectance with 650nm-1100nm. The powder of color from green to blue can be prepared by a different concentration ion-doped. The introduction of Mg2+ has great effect on red edge. With increasing of the concentration of Mg2+, the reflectance of pigments can be risen from the lower wavelength position. So that the reflectance curve of pigment can enter into the channel. And, when the concentration of Mg2+ is in the range of 0.1-0.3, the pigment can enter the near infrared channel. The infrared reflection properties of pigment would be destroyed by introduction of Ni2+.The content of Ni2+ has effect on the color of pigment. With the increasing of Ni2+ concentration, the color of pigment changed from bluish green to yellow green.