Previous work has shown that laser-induced desorption (LID) can prove useful for the determination of surface contamination. However, because of the nature of small-spot sampling utilized in the previous work, it proved rather difficult to gather statistically significant data. A solution to this problem that still allowed sampling the surface with small focused laser spots was to automate the sample manipulation, laser control, and data acquisition of the system. With the automation of the LID facility in place, a detailed study of the LID of water/heavy water (H₂O/D₂O) was undertaken. As in the earlier work, samples were irradiated with a hydrogen fluoride/deuterium fluoride (HF/DF) laser beam focused inside an ultrahigh vacuum (UHV) chamber. The molecules desorbed from the sample surface were partially contained in a glass envelope that also contained a quadrupole mass analyzer. Samples consisted of bulk-etched CaF₂ and optical thin-film coatings of CaF₂--undosed or H₂O/D₂O dosed--on a variety of substrates. Some analysis was performed on cleaved, single-crystal alkali halides. The focused laser spot size was 155 μm (l/e² diameter) for the HF laser and 138 μm (l/e² diameter) for the DF laser. Between 400 and 800 sites per sample were tested for each desorption onset analysis. A study was also performed to test the possibility of correlation between (1) laser-induced damage and defects and (2) laser-induced desorption and adsorption sites for some of the samples listed above. Attempts to deuterate and hydrate CaF₂ thin films met with limited success as laser-induced desorption samples. Other analysis techniques showed that dosing during the coating process produced a more ordered coating; in fact, dosing with H₂O reduced the optical absorption in the "H₂O" band, modified the damage morphology, and, along with a low temperature bakeout, raised the laser-damage threshold.

The deformation of a mirror's optical surface due to a spacial variation of the coefficient of thermal expansion is examined. Four types of variations of the coefficient of thermal expansion are studied. These represent variations which result after typical manufacturing and/or fabrication processes. Equations describing the deformations resulting from the variations in the coefficient of thermal expansion are derived for some of the cases. Deformations due to more complex variations in the coefficient of thermal expansion are developed empirically using data generated by the finite-element method.

A study has been carried out to investigate the effects of heat treatment on microindentation hardness, abrasion and corrosion resistance of Electroless Nickel coatings. In particular, a proprietary coating system, NIKLAD 794 has been investigated. Samples of 4130 steel have been plated according to manufacturer's specifications. The plated samples have then been subjected to an array of heat treatment temperatures and times. Post heat treatment tests have been conducted including Taber Abrasion testing, salt fog chamber testing, and Knoop microindentation hardness testing. Results of the individual tests have been compared to determine the effects of heat treatment on, and the interactions between, the parameters examined.

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The aim of this study has been to investigate the possibilities to identify lack of glue in finger joints by checking different non-destructive techniques. Specifically, this study puts emphasis on finding a method suitable for an automated and fast industry production line of home furnishing products. The methods investigated are of three main varieties: Sound/vibration Thermography Tomography The most promising method was the high-power ultrasound thermography. This method is fast and reliable, but more research is needed. It is necessary to find out if the thermography waves can penetrate deep enough. Another possible method is computed tomography. This method can take a lot of time, but the speed of scanning depends on the accuracy demanded. / Uppgiften har varit att granska möjligheterna att identifiera bristfälliga trälimningar eller helt avsaknad av lim i fingerskarvar med hjälp av olika metoder som inte förstör materialet, NDT (non-destructive testing). Undersökningen syftar speciellt till att finna en metod som är anpassad till ett effektivt produktionsflöde i industrin. Det måste där med vara en metod som med stor snabbhet kan hitta eventuella fel på produkterna. De metoder som mer omfattande har granskats är ljud/vibration, termografi och tomografi. Den metod som visat sig mest lovande är high-power ultrasound thermography. Tester måste dock utföras för att säkerställa att metoden är passande för ändamålet. Framför allt om de termografiska vågorna tränger in tillräckligt djupt. En annan möjlighet är datortomografi. Denna metod kan vara tidskrävande, men skanningshastigheten beror på hur noggrant mätresultat som erfordras. Här finns också en säkerhetsaspekt som måste beaktas, eftersom röntgenstrålar används.