Kenneth E. Nietering

Optical properties of spray-deposited tin oxide films.

Optical properties of spray-deposited tin oxide (TO) films are studied here. Optical grade TO films were deposited using monobutyl tin chloride and dibutyl tin diacetate solutions. The refractive index and extinction coefficient, n(lambda) and k(lambda), respectively, and film thickness of TO films are evaluated from spectrophotometric transmittance characteristics examined in the visible and UV regions. Since the interference effects are suppressed by the optical absorption in the near-IR region, both reflectance and transmittance spectra are used to evaluate n(lambda) and k(lambda) values. Spray-deposited TO films are found to be an indirect band gap material exhibiting an absorption minimum at ~1.0 microm (k less, similar 10(-3)), an energy gap at ~3.7 eV. A transition from a bounded electron model to a free electron model occurs at lambda approximately 1.4 microm.

Tungsten oxide films by reactive and conventional evaporation techniques

Tungsten oxide films (WO(3)) are deposited by thermal evaporation techniques using the starting materials of tungsten (W) and tungsten oxide (WO(3)). By varying deposition parameters, three main types of WO(3) film exhibiting different optical properties form. These are blue, gray, and colorless films. The samples are characterized optically and morphologically. Blue-colored samples exhibit a broad selective absorption peak around 1000nm. Absorption of gray-colored samples spreads out in the visible region in an exponential form. The refractive indices of samples are between 1.9 and 2.1. The energy gap of blue and colorless samples is 3.32 eV, but that of the gray-colored samples is 3.18 eV and smaller. X-ray diffraction studies reveal that evaporated WO(3) films are amorphous. Fourier transform infrared spectra of samples were studied to evaluate bond properties. Colorless near-stoichiometric tungsten oxide films exhibit three absorption peaks in the 1000-600-cm(-1) window. These peak locations, in terms of cm(-1) window. These peak locations, in terms of cm(-1), are 669,737, and 813. In the colored samples, these three absorption peaks split into two peaks ~20 cm(-1) apart.

NVH Performance of Lightweight Glazing Materials in Vehicle Design

Fuel economy and NVH (noise, vibration, and harshness) performance of vehicles are important parameters in a customer’s vehicle purchase decision. Lightweight vehicle designs are necessary to help with fuel economy improvements. In this research work, the weight saving potential and NVH performance of different lightweight glazing materials are investigated to help the lightweight design effort. The lightweight glazing materials included in this study are “Material A”, “Material B”, “Material C” with regular lamination, and “Material C” with acoustic lamination. The results of this research work indicate that the lightweight glazing materials have 30% to 40% weight saving potentials without NVH penalty. These materials have much higher damping properties than conventional tempered glass so they can compensate for the mass reduction influence on vehicle NVH. The tire patch noise reduction, vehicle transparency, and wind noise results of “Vehicle A” tested with different lightweight backlight designs indicate that there is almost no acoustic response difference between the tempered glass and other lightweight alternative backlight designs. Damping loss factor measurements indicate that “Material C” with acoustic PVB (polyvinyl-butyral) has the highest damping loss factor value of 37%. The “Material C” backlight with acoustic PVB is the best among all the lightweight alternatives and brings 29% weight reduction without any NVH degradation. Statistical Energy Analysis (SEA) results also indicate that it is possible to eliminate the NVH degradation by using glazing material having high material damping properties or using laminated panels having damping loss values in the range of 6% to 20%. In this paper, we only address the weight reduction and NVH performance of light weight glazing materials but not the costs or any potential assembly procedure changes.Copyright