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article i nfo Available online 16 August 2011 Silver oxovanadate powders were produced using a low temperature hydrothermal synthesis method. X-ray diffraction (XRD) and Raman microscopy revealed the formation of the α-Ag3VO4 phase, and differential scanning calorimetry (DSC) indicated that the powders underwent phase changes with the increase of temperature (formation of Ag-deficient phases). Ag3VO4 precipitates were subsequently investigated as potential high temperature solid lubricant (SL) powders that may be burnished onto textured surfaces. Textured coatings were produced by the sputter deposition of vanadium nitride (VN) thin films, followed by the fabrication of a periodic array of micro-scale dimples with reactive ion etching (RIE). The etched patterns acted as reservoirs to replenish the sliding contact with solid lubricants. The effectiveness of this new design of high temperature tribological coating was tested using a pin-on-desk tribotester. A significant decrease in the wear rate and coefficient of friction (CoF) was achieved at high temperatures (750 °C) and was maintained as a result of the storage of the Ag3VO4 phase in the dimples. After wear testing, Raman spectroscopy and XRD were used to identify the phase composition developed as a result of tribotesting. It was found that the burnished powders were more effective in enhancing the tribological properties of textured films compared to burnished/un-burnished monolithic VN coatings.

A new design of micro-evaporators, with 45 channels (View the MathML source100?m deep) and diamond-shaped fins (View the MathML source40?m wide, View the MathML source160?m long, View the MathML source20?m separation), is fabricated by anodic bonding of silicon and glass wafers, in a five masks process. This new design improves stability of the working conditions, and has a localized hot zone in the main part of the device. The measured absorbed heat includes the energy that heats up the coolant (water) from 25 to View the MathML source100?C (roughly 300 J/g) and the latent heat of evaporation (2400 J/g). The latter one is a dominant term, and heat absorption is significantly increased at fin temperatures above the water boiling point.

This paper describes an innovative optimization approach that offers significant improvements in performance over existing methods to solve shape optimization problems. The new approach is based on two-stages which are (1) Taguchi's robust design approach to find appropriate interval levels of design parameters (2) Immune algorithm to generate optimal solutions using refined intervals from the previous stage. A benchmark test problem is first used to illustrate the effectiveness and efficiency of the approach. Finally, it is applied to the shape design optimization of a vehicle component to illustrate how the present approach can be applied for solving shape design optimization problems. The results show that the proposed approach not only can find optimal but also can obtain both better and more robust results than the existing algorithm reported recently in the literature.