Search

A Fe–Cr alloy, used for metallic interconnects, was coated with a protective layer of lanthanum strontium manganite (LSMO) using the aerosol deposition method (AD). The effects of the LSMO protective layer, which was coated on the Fe–Cr interconnects using AD, on the area specific resistance (ASR) during high temperature oxidation and the Cr evaporation behaviors were systematically investigated in this paper. The microstructures, morphologies, and compositions of the oxidized scales that appeared on the LSMO-coated Fe–Cr alloy after annealing at 800 °C for 750 h in air were examined using SEM equipped with EDS. The EPMA mapping of the LSMO-coated Fe–Cr interconnects undergoing long term, high-temperature oxidation was used to explain the formation layers of the oxidized scale, which consists of (Mn,Cr) 3 O 4 and Cr 2 O 3 layers. Moreover, the experimental results revealed that the AD process is a potential method for preparing denser protective layers with highly desirable electrical properties for metallic interconnects.

Al-Si alloys, with such excellent properties as low weight, low thermal expansion coefficient, and high wear-resistance, are ideal materials for the automobile and aerospace industries. However, their applications have been hampered by the coarsening of the primary-Si particles in Al-Si alloys. In this study, simple plastic deformation was used to reduce primary-Si particles and to improve the wear-resistance and mechanical strength of Al-Si alloys. Experimental results showed that mechanical rolling decreased the grain size of primary-Si particles in Al-Si alloys and reduced the variation in silicon particle size. After 60%-roll-reduction, the alloy showed an improved tensile strength of 340 MPa, which is attributed to the work hardening of the aluminum matrix and the dispersion strengthening of the primary-Si particles. Data from wear-resistance testing showed that rolling led to a reduction in wear loss. This improvement in wear resistance is due to the particle size refinement of silicon at a high percentage-roll-reduction.

This research studies a brand new Magnesium Lithium Alloy, LAZ1151, with trace Sc additions. The mechanical properties and microstructures of the as-cast and alloys after three and six month aging were observed and analyzed. Microstructure and XRD confirms the existence of α phase precipitates (Mg rich) in both as-cast and aging specimens of the alloy. Grain growth was observed in the alloy after room temperature aging. The tensile strength of the as-cast LAZ1151 is 147 MPa; the value is decreased to 135 MPa after six month aging, showing typical room temperature softening. Strengthening via the use of cold rolling was tried; a maximum tensile strength of 180 MPa was achieved after 90% rolling reduction, which is mainly due to strain hardening.

An amperometric sensor for monitoring ethanol concentration using a Ni–Pt alloy electrode has been developed. The films of Ni–Pt alloy were electrodeposited under various potentials on an Au/Al2O3 substrate. To examine the effects of Ni–Pt alloy films on the sensing performance, the electrodes with various Ni:Pt atomic proportions of 100:0, 25:75, 70:30, 82:18 and 0:100 were prepared and tested. X-ray diffraction and scanning electron microscope analyses indicate that Ni atoms of Ni–Pt alloy electrodes are inserted in the Pt lattice and a pyramid-like structure is formed with an increase of Pt content in the film. All the prepared electrodes have a linear relationship between response current and ethanol concentration for the detection range of 50 to 300 ppm ethanol in alkaline solutions. With an increase of Pt content in the film, the response time of the Ni–Pt alloy electrodes was reduced whereas the sensitivity was decreased. The sensor with 70 at.% Pt in the film was most stable with the duration over a 63-day-period. The sensitivity of the Ni–Pt alloy electrodes for detecting glucose, various alcohols and acids have also been studied.

Four metallic alloys, namely 2205 duplex stainless steel (2205DSS), ZMG232, and stainless steels SS430 and SS304 are investigated for use as interconnects in solid oxide fuel cells (SOFCs). A La0.67Sr0.33MnO3–δ (LSMO) film is deposited on these metallic-alloy substrates using a pulsed-DC magnetron sputtering system in the reactive mode, leading to the formation of a cubic perovskite structure. The coated alloys are then subjected to oxidizing heat treatments in air at 600 °C, 700 °C, 800 °C, and 900 °C, and their microstructures as well as electrical resistances are evaluated. The electrical resistance measurements are performed at 800 °C, and the area-specific resistance (ASR) of the film-coated 2205DSS alloy is found to be less than that of the uncoated alloy. This is because a thick layer of Cr2O3 and a (Mn, Fe)Cr2O4 spinel phase layer are formed, and some divalent metallic ions migrate into the Cr2O3 layer. It is found that alloys coated with a thin film of LSMO are more suitable for use as metallic interconnects in SOFCs with intermediate-temperature operating ranges.

Corrigendum to “Determination of alcohols using a Ni–Pt alloy amperometric sensor” [Thin Solid Films 516 (2008) 5210–5216] Jian-Jia Huang , Weng-Sing Hwang ⁎, Yu-Ching Weng , Tse-Chuan Chou b,c a Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan b Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan c Department of Chemical Engineering, Tatung University, Taipei, Taiwan