| Solid and liquid thin films have been analyzed by infrared emission Fourier microspectrophotometry. The apparatus used in a commercial absorption instrument modified to an emission instrument, comprising a rotating polarizing device, a miniature blackbody temperature reference adjustable in temperature and radiant flux and a microscope lens with a high numerical aperture in the entrance system for increased sensitivity and resolution. In addition, new measurement methods for the application of this hardware have been developed.;With the same instrument solid deposits on aircraft fuel lines were studied. These materials were deposited in a preferred direction. Despite the strong background radiation and the presence of a multitude of compounds, the spectral contrast was sufficient to establish a relationship betwen fuel and deposit composition. Comparison of a 1 year old sample with a sample exposed to accelerated oxidation showed little difference. The originally crystalline structure became amorphous and therefore more tacky, which is very undesirable. This result shows the ractivity of initial deposits and the need for storing them with care.;Studies of lubricant behavior in a simulated ball bearing showed the alignment of the fluid molecules in the Hertzian area. Polyphenyl ether contaminated with 1% 1,1,2-trichloroethane required far lower shear rates for the same degree of alignment than without contaminant. The experiment was run with 440 C stainless steel balls and 440 C balls coated with TiN, a chemically inert material. In both cases, the alignment was strongly influenced by the presence of the contaminant. The results showed (i) the dependence of alignment of fluid molecules on flow and not on adsorption at metallic surfaces (ii) phase separation between lubricant and additive under high pressure which results in two-phase flow and (iii) reduction in traction of torque-transmitting (traction) fluids. Measurements of phase separation, by differential thermal analysis and in a high pressure cell, and traction measurements confirmed the spectral results. |
